## SOUTH COAST AIR QUALITY MANAGEMENT DISTRICT

SOUTH COAST AIR QUAL ITY MAN A GEMENT DISTRICT

5 YEAR NETWORK ASSES S MENT

July 2010

Prepared by

Rene M. Bermudez Principal Air Quality Instrument Specialist

Philip M. Fine Atmospheric Measure ments ManagerAir Quality Monitoring Network Plan

– July 2010

i 

## Table of Contents

Page

I Introduction

......... ........................ ............................................................ 1

II Site Assessments

................................................... ............... ...... ...... . 21

III Network Assessment

.................................... ............. ........................... 4 4

IV Potential AQMD Network Changes

............ ........... ...... ... ......................... 8 61 

## I. INTRODUCTION

A periodic Network Assessment of the Ambient Air Monitoring Network is required by Federal Regulations as a key tool to help ensure that criteria pollutants are measured in important

loc a tions and that mon itoring resources are used in the most effective and efficient manner to meet the needs of multiple stakeholders. Network assessments help identify new data needs and

ass o ciated technologies, find opportunities for consolidation of individual sites into

m ulti

- pollutant sites, and identify geographic areas where network coverage should be increased or decreased based on changes in the population and/or emissions. The Environmental Protection Agency (EPA) requires that local agencies perform an assessment o f the air quality surveillance system every 5 years to determine, at a minimum, if the network meets the monitoring objectives defined in Title 40, Part 58, Section 10 of the Code of Federal Regulations ( 40 CFR § 58 ) Appendix D, whether new sites are neede d, whether existing sites are no longer needed and can be terminated, and whether new technologies are appropriate for incorporation

into the Ambient Air Monitoring Network . This r e port describes the assessment of the Ambient Air Monitoring Network operat ed by the South Coast Air Quality Management District ( AQMD ) and fulfills the requirements for a periodic network review as listed in 40 CFR § 58.10

. Regulation requires that the report be submitted to the EPA by July 1 2010.



### SOUTH COAST AQMD HISTORY

Ea rly efforts to control air pollution in California began in Los Angeles with legislation proposing counties establish Air Pollution Control Boards. The proposed legislation was approved and signed into law on June 10, 1945 and the Los Angeles County Air P ollution Control District was established in October 1947. Orange County, San Bernardino, and

Riverside formed Air Pollution Control Districts by 1957. Realizing that air pollution was a regional problem, the four counties merged to form the South Coast AQMD in 1977. Geographically, South Coast AQMD encompasses 10,750 square miles and is located within t he South Coast Air Basin (SCAB ) , which is the second most populated area in the United States. Southern California consistently records the highest leve ls of ozone (O3) and particulates in the

nation. As the local air pollution co n trol agency, South Coast AQMD is responsible for controlling air quality emissions from various sources to meet National Ambient Air Quality Standards (NAAQS) as well as ambien t air qual i ty standards established by the California Air Resources Board (CARB). Every three years an Air Quality Management Plan is developed and adopted by the South Coast AQMD Board, which describes what actions will be taken to bring

the SCAB into co mpliance with State and Federal clean air standards. To assess compliance

with State and Federal standards

, a surveillance network of 40 permanent air monitoring sites are maintained to measure criteria pollutants

. The air quality data collected by the s urveillance network is used for comparison to air quality standards, developing control strategies and regulations to meet those standards, and to provide public information on current and forecasted air quality.

South Coast AQMD operates 40 permanent air monitoring sites in the SCAB and a portion of the Salton Sea Air Basin in Coachella Valley. This area includes Orange County and the non

- desert portions of Los A n geles, Riverside, and San Bernardino Counties. South Coast AQMD also

operates numerous temp orary monitoring sites for shorter

- term objectives such as air toxic studies, community

- based monitoring, and compliance with air quality regulations.2



### MONITORING NETWORK H ISTORY
The earliest air monitoring station was operated by the Los Angeles County A ir Pollution

Co n trol District at 5201 Santa Fe St. before being relocated to the agency's headquarters at 434 South San Pedro in 1955. The oldest monitoring location still in existence is located in Azusa and opened in 1957. The newest permanent site was added in 2008 in Compton to replace the Lynwood air monitoring location. Table 1 provides a list of monitoring locations, EPA Air Quality System (AQS) site codes, and the pollutants measured at each site. Table 2 provides monitoring objectives and the s patial scale of representativeness for monitors at each site. Table 3 describes the monitoring purpose for monitors at each site. Table 4 describes the monitoring objective, purpose, and spatial scale for continuous particulate analyzers at each site. M onitoring

o bjectives are defined as:

Background Level monitoring is used to determine general background levels of air pollutants as they enter the SCAB.

High Concentration monitoring is conducted at sites to determine the highest concentration

of an air pollutant in an area within the monitoring network. A monitoring network may have multiple high concentration sites (i.e., due to varying meteorology year to year).

Pollutant Transport is the movement of a pollutant between air basins or areas within an air basin. Transport monitoring is used to assess and mitigate upwind areas when a

tran s ported pollutant affects neighboring downwind areas. Also, transport monitoring is used to determine the extent of regional pollutant transport among populated areas and to

rural areas.

Population Exposure monitoring is conducted to represent the air pollutant concentrations a populated area is exposed to.

Representative Concentration monitoring is conducted to represent the air quality

conce n trations for a pollutan t expected to be similar throughout a geographical area. These sites do not necessarily indicate the highest concentrations in the area for a particular pollutant.

Source Impact monitoring is used to determine the impact of significant sources or source categories of air quality emissions on ambient air quality. The air pollutant sources may be stationary or mobile.

Trend Analysis monitoring is useful for comparing and analyzing air pollution

concentr a tions over time. Usually, trend analysis show the progress or lack of progress in impro v ing air quality for an area over a period of many years.

Site Comparison monitoring is used to assess the effect on measured pollutant levels of moving a monitoring location a short distance (usually less than two mil es). Some

mon i toring stations become unusable due to development, change of lease terms, or eviction. In these cases, attempts are made to conduct concurrent monitoring at the old and new site for a period of at least one year in order to compare polluta nt concentrations.3

Real Time Reporting/Modeling is used to provide data to the EPA’s AIRNOW system, which reports conditions for air pollutants on a real time basis to the general public. Data is also used to provide accurate and timely air quality foreca st guidance to residents of the

South Coast basin.

Multiple purposes for measuring a pollutant at a particular site are possible. There is some

ove r lap between monitoring objectives as defined by the EPA and given in Table 2, and the monitoring purposes provided in Table 3.

A brief description of the network for each criteria pollutant monitored and monitoring program is provided below:

Ozone

The South Coast AQMD operates 30 sites where ozone (O3) measurements are made as part of the Air Monitoring Netwo rk. Figure 2 in Section III shows the spatial distribution

of these sites.

Carbon Monoxide

Ambient carbon monoxide (CO) monitors measure concentrations at 26 locations. Figure 5 in Section III shows the spatial distribution of these sites.

Nitrogen Dioxi de

The nitrogen dioxide (NO2) network consists of 26 sites. These sites are mostly located in areas of highest NO2 concentration. The spatial distribution of NO2 monitors is shown in Figure 7 , Section III

.

Sulfur Dioxide

Sulfur dioxide (SO2) monitors are located at 7 sites. Figure 9 in Section III shows the spatial distribution of the sites.

Particulate Lead

Total suspended particulate (TSP) lead (Pb) measurements are collected at 19 sites as part

of the ne t work. Five sites are source

- oriented and the r emaining 10 sites are population

oriented. The spatial distribution of these sites is shown in Figure 11 , Section III

.

PM10

Size

- selective inlet high volume samplers are operated at 22 sites to meet the requir e ments for PM10 Federal Reference Method (FRM) sampling. Of the 22 sites, 13 also include continuous PM10 analyzers. Figure 13 in Section III shows the spatial distribution of the sampling sites.

PM2.5
A network of 17 FRM samplers was first implemented in January 1999. Since then, the

network has e xpanded to include 20 sites depicted in Fi g ure 16 , Section III and listed in Table 5. Continuous PM2.5 Met One Beta Attenuation Monitors (BAMs) were first deployed in 2001. Sixteen continuous PM2.5 monitors are now operating in the Basin.4

PM2.5 speciat ion sampling is also a part of the South Coast AQMD PM2.5 monitoring program. The network includes two Speciation Trends Network (STN) samplers and four permanent South Coast AQMD speciation mo n itoring locations.

The following is a brief description of sp ecific programs that are operated within the Ambient Air Monitoring Network :

Photochemical Assessment Monitoring Stations (PAMS)
The PAMS network was initiated in June 1994 and consists of 7 air monitoring locations.

PAMS are used to collect data for a ta rget list of Volatile Organic Compounds (VOC s )

, N itrogen Oxides (NO x) , Reactive Oxides of Nitrogen (NOy), O3, and meteorological measurements. The PAMS network was established to provide information about the effectiveness of control strategies, emissions tracking, trends

, and exposure. To address regulatory changes, site

- specific observations from the recent National PAMS Network

A s sessment, and to address potential synergies between programs, South Coast AQMD made changes in June 2009 to the PAMS monito ring network based on specific

reco m mendations:

 Burbank was reclassified from Type 2/1 to Type 2. This change addressed the

National PAMS Network Assessment observation that Burbank should be reclassified to a Type 2 precursor site. The recommendation is consistent with the heavily urbanized/industrialized area, which is impacted by high levels of O3 precursor emissions.

 Santa Clarita was reclassified as Type 3 from Type 2. Although the National

PAMS Ne t work Assessment observed that Santa Clarita wa s consistent with a Type 2 site, recent data was more consistent with a Type 3 maximum O3 concentration site rather than a Type 2 O3 precursor site.

 Banning was relocated to Los Angeles (Main). The National PAMS Network Assessment observed that Banning ha d the lowest O3 concentrations of all the Type 2 sites and should be reclassified to a Type 3 or 4 site. Instead, to create synergies between programs, South Coast AQMD relocated the Banning PAMS site to the Los Angeles (Main) site as Type 2. This satisf ies the EPA

recommendation for use of the same monito r ing platform and equipment to meet the objectives of multiple programs. Los Angeles (Main) is also a National Air Toxics Trends Station (NATTS), a future National Core

- Multi

- pollutant Monitoring Station (NCore), and an STN site.

 Azusa was reclassified from Type 3 to Type 2. This proposed change addresses the National PAMS Network Assessment observation that Azusa has high VOC

and NO x concentrations, with lower O3 concentrations. The site now more

close ly resembles a Type 2 O3 precursor site.

 Upland was relocated to the Rubidoux site. The National PAMS Network Assessment observed that Upland was no longer consistent with a Type 4 site and

reco m mended reclassification to Type 3. South Coast AQMD relocat ed the Upland PAMS site to Rubidoux as a Type 3 location where synergies can be created among the NATTS , NCore, and the STN programs.5  LAX Hastings and Pico Rivera remained unchanged.

Currently, manual VOC canisters are in operation at the Azusa, LAX Hasti ngs, Rubidoux, Los Angeles (Main)

, and Santa Clarita air monitoring stations. During the intensive season from July 1 until Se p tember 30, VOC canisters are run every three hours for a period of twenty

- four hours every 3rd day and a twenty

- four hour sample is run every 6th day. During the non

- intensive season from October 1 through June 30, twenty

four hour VOC canister samples are run every 6th day.

At Los Angeles (Main) and Santa Clarita air monitoring stations, during the intensive season from July 1 u ntil September 30, carbonyl samples are run every three hours for a period of twenty

- four hours every 3rd day and a twenty

- four hour sample is run every 6th day. During the non

- intensive season from October 1 through June 30, twenty

- four hour carbonyl sam ples are run every 6th day.

Automated gas chromatography flame ionization detector (GC \ FID) VOC systems are in operation at the Pico Rivera and Burbank air monitoring stations. During the intensive sampling season from July 1 until September 30, the GC \ F ID is run to collect 3

- hour samples and twenty

- four hour VOC canisters are run every 6th day. Like the other PAMS sites, carbonyl samples are run every three hours with one additional twenty

- four hour sample run every 6th day. During the non

- intensive se ason from October 1 through June 30, the GC/FID is idle and twenty

- four hour VOC canister samples are run every 6th day and twenty

- four hour carbonyl samples are run every 6th day. Rubidoux is a collocated site for VOC canister sampling and Pico Rivera is a collocated site for VOC canister and carbonyl sampling.

The first South Coast AQMD upper air meteorological monitoring station was established at Los Angeles International Airport (LAX) in 1994. Subsequent upper air

stations include Ontario Internatio nal Airport (ONT) installed in 1996, Moreno Valley (MOV) installed in 2001 at the Moreno Valley Municipal Water Treatment Plant in

R i verside County, Irvine installed at the University of California Research and Extension Center in 2006, and Pacoima at Whit eman Airport during May 2007. The upper air

st a tions use a combination of remote sensing and surface meteorological instrumentation, including the Vaisala (formerly Radian/URS) LAP

- 3000 radar wind profiler with a Radio Acoustic Sounding System (RASS), the Atmospheric Systems Corporation (formerly AeroVironment Inc.) mini Sodar acoustic wind profiler, and tower

- mounted meteorolog i cal measurements of wind, pressure, temperature, relative humidity, solar

radiation and ultraviolet radiation.

The PAMS network monitoring objectives and requirements are summarized in Table 6.

NATTS

The NATTS program was developed to fulfill the need for long

- term hazardous air pollutant (HAP) monitoring data of consistent quality nationwide. South Coast AQMD

has conducted severa l air toxics measurement campaigns in the past, which demonstrated the variety and spatial distribution of air toxics sources across SCAB. A single air toxics6

me a surement site cannot reflect the levels and trends of air toxics throughout the b asin.

For th is reason, two NATTS sites are used to characterize the SCAB’s toxics levels. The first site is a central urban core site in Los Angeles that reflects concentrations and trends due primarily to urban mobile source emi s sions. A second, more rural, inland site at Rubidoux captures the transport of pollutants from a variety of upwind mobile and industrial sources in the most populated areas of the air basin. NATTS monitoring began in February 2007 and continues at the Los Angeles (Main) and Rubidoux air mon itoring sites. During April 2010, a system audit was co n ducted by the EPA, which assessed the South Coast AQMD NATTS program. The audit found no major issues with the operation of the network but recommended implement a tion of blanking and low level

conce ntration challenge samples. Blanking will be implemented in 2010 and low level challenge samples will be implemented in 2011.

NCore

In October 2006, the EPA issued amendments to ambient air monitoring regulations for criteria pollutants. One of the most significant changes in regulations was the requirement to establish NCore stations. These stations provide pollutant data at much lower detection limits than the existing air monitoring network. NCore monitoring regulations require that South Coast AQMD make NCore stations operational by January 1, 2011. To meet this goal, South Coast AQMD has installed trace level analyzers for CO, NOy, SO2

, and Continuous FEM BAM PM2.5 in Rubidoux and Los Angeles (Main) , both of which are exi sting STN and NATTS sites.



### NETWORK ASSESSMENTS

Regulatory Requirements The earliest air monitoring sites in the United States were established over 50 years ago

with sites added to the national network as needed to fulfill Federal monitoring requirements and other objectives. Sin ce the time of inception, air quality, population, and behaviors have changed, and there is a general need for re

- evaluation of the overall network design and objectives. Recognizing this need, the U.S. EPA finalized an

amendment to the ambient air monito ring regulations on October 17, 2006 to address the issue. In the amendment, the U.S. EPA required S tate and local air monitoring agencies

to conduct a ne t work assessment once every five years, with the first assessment due by July 1, 2010.

The state or where applicable local agency shall perform and submit to the EPA Regional Administrator an assessment of the air quality surveillance system every 5 years to determine, at a minimum, if the network meets the monitoring objectives defined in 40 CFR § 58

A p pendix D, whether new sites are needed, whether existing sites are no longer needed and can be terminated, and whether new technologies are appropriate for incorp o ration into the Ambient Air Monitoring Network

. The Network Assessment must consider the abi lity of existing and proposed sites to support air quality characterization for areas with relatively high populations of susceptible individuals, and for any sites7 that are being proposed for discontinuance. The assessment must also

consider the effect o n data users other than the agency itself, such as nearby States and Tribes or health effects studies. For PM2.5, the assessment must also identify needed changes to population

- oriented sites. The state or where applicable l o cal agency must submit a copy of this assessment along with a revised annual network plan to the Regional Administrator. (40 CFR § 58.10d 236)

In general, a ir monitoring networks must be designed to meet three basic objectives according to 40 CFR § 58. First, they must provide air pollution data to the general public in a timely manner. Second, they must support compliance with ambient air quality standards shown in Table 7, and third , they must support research studies on health effects assessments. In order to achieve these goa ls, networks must meet the 40

CFR § 58 Appendix D , Network Design, and Appendix E, Probe Siting Criteria.

Network Design Criteria

Ambient air monitoring network design is specified by U.S. EPA and include monitoring objectives and general criteria, as out lined in 40 CFR § 58 Appendix D . Each objective is related to a specific type of air monitoring site, and air monitoring networks must be designed for each criteria po l lutant and must meet specific objectives. Monitoring objectives and corresponding scal es of representativeness are shown in Table 8.

Minimum Number of Sites

As a general requirement, the U.S. EPA specifies the minimum numbers of sites required in a network based on the latest census population data and design value concentrations for speci fic criteria pollutants. The minimum number of O3 sites required is based upon the Metropolitan Statistical Area (MSA) population and the most recent 3

- year design value as shown in Table 9. As of July 2009, there were no minimum requirements for the

num ber of CO, NO2, and SO2 mo n itoring sites in an air monitoring network, other than NCore requirements. New regulations for NO2 and SO2 require minimum numbers of monitoring locations taking effect in 2013, but they will not be addressed in this

a ssessment. Local a gencies are required to conduct ambient air Pb monitoring taking into

account:

 Pb sources which are expected or have been shown to contribute to a maximum Pb concentration in ambient air in excess of the NAAQS.

 The potential for population exposur e and logistics.

At a minimum, there must be one source oriented SLAMS site located to measure the maximum Pb concentration in ambient air resulting from sources of Pb, which emit 1.0 or more tons per year based on the latest National Emission Inventory (NEI) or other justifiable methods or data. Local Agencies are also required to conduct Pb monitoring

in each Core Based Statistical Area ( CBSA ) with a population equal to or greater than 500,000 people. At a minimum, there must be one non

- source oriente d SLAMS site located to measure neighborhood scale Pb concentrations in urban areas impacted by re

entrained dust from roadways, closed industrial sources of Pb, hazardous waste sites,8

construction and demolition projects and other fugitive sources of Pb. The number of PM10 sites required is based upon MSA population data and shown in Table 10. The number of PM2.5 sites required is based upon MSA population data and shown in Table 11. The final number of sites in a network is subject to U.S. EPA Regional Administrator approval via the Annual Network Plan.

Probe Siting Criteria
Once a site has been selected based on monitoring objective and spatial scale, the site must also meet specific siting criteria for each spatial scale and each pollutant as specified in 40 CFR § 58 Appendix E . These criteria include the placement of the pollutant measuring device inlet probe, spacing from minor sources of pollution, spacing from obstructions to the monitoring probe, spacing from trees, spacing from roadways, probe ma terial and residence time.

Horizontal and Vertical Placement

Inlet probes must be placed both horizontally and vertically so that at least 90 percent of the area over which pollutants are being measured and averaged is 1 meter (m) from walls or any support ing structure. For measurement of par ticulates, a minimum of 2 m is required. Inlet probes must also be placed between 2 m and 15 m above the ground level for all criteria pollutants at the neighborhood scale. Particulate probe inlets at middle and

micr o scale are to be between 2 m and 7 m above ground level. Near roadway, and CO

micro scale measurements are to be 3 +/

- 1⁄2 m above ground level. A summary of horizontal and vertical placement is shown in Table 12.

Spacing from Minor Sources

Spacing requir ements are dependent upon the monitoring objective. If the objective is to

measure the impact of a stationary source’s primary pollutant emissions, then the probe may be l o cated close to the source and be classified as a micro

- scale site. A micro

- scale

s ite typically represents an area up to 100 m in size. If the objective is to measure pollutants over a larger area such as a neighborhood or city, then the monitoring location should be located away from minor sources of pollutants so as not to impact air quality data collected at the site. Particulate matter sites should not be located in unpaved areas where windblown dust can influence data collected. Special attention should be placed on horizontal and vertical probe placement from furnace or incinera tion flues to prevent scavenging of O3 by NO and O3 reactive hydrocarbons.

Spacing from Obstructions

Buildings and other obstacles may scavenge SO2, O3, or NO2 and restrict airflow for any

po l lutant measured. To prevent this influence, the probe must ha ve unrestricted airflow and be located away from obstacles. The distance from an obstacle to the probe should be twice the height that the obstacle protrudes above the inlet. For particulate sampling, a minimum of 2 m separation is required between monit ors, wa lls, parapets, and structures.

Spacing from Trees

Trees can scavenge SO2, O3, and NO2 by adsorption and provide a surface for particle

d e position. Trees also act as obstructions and special attention should be made to adhere9

to correct spacing. To reduce interference, the probe inlet should be at least 10 m from the drip line of the tree. For micro

- scale sites, no trees should exist between the probe inlet and the source being measured.

Spacing from Roadways

O3 and NO2 in particular are suscept ible to interference from roadway emissions. When siting monitors for neighborhood scale and urban scales, it is important to minimize roadway interference. Recommended spacing from roadways for O3, NO2, CO, and PM samplers are summarized in Tables 13, 1 4, and Figure 1. Recent requirements for micro

scale NO2 monitoring near roadways are not addressed in this assessment.

EPA Guidance and Memos

To facilitate the Network Assessment , the EPA issued guidance for local air quality agencies. During March 199 8, the EPA Office of Air Quality Planning and Standards (OAQPS) issued State and Local Air Monitoring Stations (SLAMS), National Air Monitoring Stations (NAMS)

, and PAMS Network Review Guidance. Guidance advocated examination of compliance with Network De sign Criteria, monitoring obje c tives, and minimum number of sites required. Guidance also recommended

examination of 40 CFR § 58 Appendix E Probe Siting Criteria. In February 2007, the EPA issued Ambient Air Monitoring Network Assessment Guidance, which included analytical techniques for assessments of Ambient Air Monitoring Network s. In the guidance, the EPA summarized the context of network assessments, provided an overview of requirements in 40 CFR § 58, and an overview of the assessm ent process.
The EPA provided steps in the assessment process and technical approaches including identification of monitoring needs, correlation analysis, and pop ulation change in order to

assess high and low value monitors. The final step in the guidance was to suggest changes to the network, obtain input from State

, Federal , and local stakeholders, and revise recommendations based on input.

EPA Tools To supplement guidance, the EPA presented an overview of the n etwork a ssessment process at the 2009 National Ambient A ir Monitoring Conference. Training focused on the process of co n ducting network assessments, providing guidance on analytical techniques used for assessments, and emphasized the goal of identifying and removing

low value monitors such that resources can b e re

- allocated to areas that are under

represented. To further aid in the process, the following tools were made available that are used in this analysis:

Population Animation The population animation tool is a Google Earth display that shows the change in population over 19 years relative to the 1990 population at the census tract level. Accompanying the population changes are the monitoring network changes from

1990 to 2008. The sites will be di s played as either black circles or gray triangles

represe nting active and inactive sites, respectively. Clicking on a site gives details of the sites start and end year. The animation serves as clear e x ample of how populations have changed within the country over the past 19 years and how the monitoring networ ks have evolved to serve those shifting populations. In10 many cases around urban areas across the country, the population has shifted away from the urbanized core to the suburbs and the mo n itoring networks have not evolved to take into account this change.

Correlation Matrix Analysis

The Correlation Matrix Anal y sis shows the correlation, relative difference, and distance between pairs of sites within a mon i toring network. The purpose of the analysis/tool is to provide a means of determining possible red undant sites that could be removed if pollution trends in that area are captured adequately by a nearby site.11

TABLE 1 Ambient Air Monitoring Locations

Location AQS No. Pollutants Monitored Start Date

Anaheim 060590007 CO,NO2,O3,PM10,PM2.5 08/01

ATSF ( Exide) 060371406 Pb 1/99

Azusa 060370002 CO,NO2,O3,PM10,PM2.5,SO4 01/57
Banning Airport 060650012 NO2,O3,PM10, PM2.5 04/97
Big Bear 060718001 PM2.5 02/99

Burbank 060371002 CO,NO2,SO2,O3,PM10,PM2.5 10/61

Closet World (Quemetco) 060371404 Pb 10/08
Comp ton 060371302 CO,NO2,O3,Pb,PM2.5 01/04

Costa Mesa 060591003 CO,NO2,SO2,O3 11/89

Crestline 060710005 O3,PM10 10/73

Fontana 060712002 CO,NO2,SO2,O3,PM10,PM2.5,SO4 08/81

Glendora 060370016 CO,NO2,O3,PM2.5,PM10 08/80

Indio 060652002 O3,PM10,PM2.5 01/83

La Habra 060595001 CO,NO2,O3 08/60

Lake Elsinore 060659001 CO,NO2,O3,PM2.5,PM10 06/87
LAX Hastings 060375005 CO,NO2,O3,PM10,Pb,SO4 04/04
Long Beach (North) 060374002 CO,NO2,SO2,O3,PM10,PM2.5,Pb,SO4 10/62
Los Angeles (Main St.) 060371103 CO,NO2,SO2,O3,P M10,Pb,PM2.5,SO4 09/79
Mira Loma (Jurupa) 2 060650004 CO,NO2,O3,PM10 10/93

Mira Loma (Van Buren) 060658005 CO,NO2,O3,PM10,PM2.5 11/05
Mission Viejo 060592022 CO,O3,PM10,PM2.5 06/99

Norco 060650003 PM10 12/80

Ontario Fire Station 060710025 PM10,PM2.5 01 /99
Palm Springs 060655001 CO,NO2,O3,PM10,PM2.5 04/71

Pasadena 060372005 CO,NO2,O3,PM2.5,SO4 04/82

Perris 060656001 O3,PM10 05/73

Pico Rivera #2 060371602 CO,NO2,O3,Pb,PM2.5,SO4,PM10 09/05

Pomona 060371701 CO,NO2,O3 06/65

Redlands 060714003 O3,PM10 0 9/86
Rehrig (Exide) 060371405 Pb 11/07

Reseda 060371201 CO,NO2,O3,PM2.5 03/65
Riverside (Magnolia) 060651003 CO,Pb,PM2.5,SO4 10/72

Rubidoux 060658001 CO,NO2,SO2,O3,PM10,Pb,PM2.5,SO4 09/72

San Bernardino 060719004 CO,NO2,O3,PM10,Pb,PM2.5 05/86

Santa C larita 060376012 CO,NO2,O3,PM10,PM2.5 05/01
South Long Beach 060374004 PM10,Pb,PM2.5,SO4 06/03

Temecula 1 TBD O3, PM2.5
Uddelholm (Trojan Battery) 060371403 Pb 11/92
Upland 060711004 CO,NO2,O3,Pb,PM2.5,PM10,SO4 03/73
Van Nuys Airport 060371402 Pb 1/10
West Los Angeles 060370113 CO,NO2,O3,SO4 05/84

1 Site to begin operation in 2010

2 Site to be closed in 2010 or 201112

TABLE 2 FRM/FEM Criteria Pollutant Monitoring Objective and Spatial Scales

MONITORING OBJECTIVE SPATIAL SCALE

HC

– High Concentration s MI

– Microscale

RC

– Representative Concentrations MS

– Middle Scale

IM

– Impact NS

– Neighborhood Scale

BL

– Background US

– Urban Scale

Location CO NO2 SO2 O3 PM10 PM2.5 Pb

Anaheim NS/RC US/RC NS/RC NS/RC NS/RC ATSF (Exide) MI/IM

Azusa NS/R C US/RC US/HC NS/RC NS/RC Banning Airport NS/RC NS/RC NS/RC Big Bear NS/RC

Burbank NS/HC NS/RC NS/RC US/HC NS/RC NS/RC Closet World ( Quemetco ) MI/IM Compton MS/HC MS/RC NS/RC NS/RC NS/RC

Costa Mesa NS/RC NS/RC NS/RC NS/RC

Cr estline NS/HC NS/RC

Fontana NS/RC US/RC NS/RC US/RC NS/HC NS/RC

Glendora NS/RC NS/RC NS/HC

Indio NS/RC NS/HC NS/RC

La Habra NS/RC US/RC NS/RC

Lake Elsinore NS/RC NS/RC NS/RC LAX Hastings MS/RC MS/RC NS/RC MS/RC NS/RC NS/RC

Lo ng Beach ( North ) MI/HC MS/RC NS/HC MS/RC MI/RC NS/HC MI/RC Los Angeles ( Main St. ) NS/RC NS/HC NS/RC NS/RC NS/RC NS/HC NS/RC Mira Loma ( Jurupa ) 2 NS/RC NS/RC NS/RC NS/HC Mira Loma ( Van Buren ) NS/RC NS/RC NS/RC NS/HC NS/RC Mission Viejo NS/RC NS/RC NS/RC NS/RC

Norco NS/RC

Ontario Fire Station NS/HC NS/RC Palm Springs NS/RC NS/RC NS/RC NS/RC NS/RC

Pasadena MS/RC MS/HC NS/RC NS/RC

Perris NS/RC NS/RC

Pico Rivera #2 NS/RC NS/HC NS/HC NS/RC NS/RC

Pomona MI/RC MS/RC MS/HC

Redlands NS/RC NS/RC Rehrig (Exide) MI/IM

Reseda NS/RC US/RC US/HC NS/RC

Riverside MI/HC US/RC NS/RC MI/HC

Rubidoux MS/RC US/RC NS/RC US/HC NS/HC NS/HC NS/RC

San Bernardino MS/RC US/RC NS/HC NS/HC NS/RC NS/RC

Santa Clarita NS/RC NS/RC US/HC NS/RC NS/RC South Long Beach NS/HC NS/RC NS/HC

Temecula 1

Uddelholm ( Trojan Battery ) MI/IM Upland NS/RC NS/RC NS/RC NS/RC Van Nuys Airport MI/IM West Los Angeles NS/RC MS/HC MS/RC

1 Site to begin operation in 2010

2 Site to be closed in 2010 or 201113

TABLE 3 FRM/FEM Criteria Pollutant Monitoring Purposes

MONITORING PURPOSE

BK

– Background Level RC

– Representative Concentration

HC

– High Concentration SPM

– Special Purpose Monitoring

TP

– Pollutant Trans port TR

– Trend Analysis

EX

– Population Exposure CP

– Site Comparisons

SO

– Source Impact

Location CO NO2 SO2 O3 PM10 PM2.5 Pb

Anaheim TR TR/RC TR TR TR/EX ATSF (Exide) SO

Azusa TR TR/RC TR TR TR/EX Banning Airport TP/RC TP TP Big Bea r EX/SO/TP Closet World (Quemetco) SO

Burbank TR TR/RC TR TR TR TR/EX Compton TR/HC TR/RC TR/RC EX/RC EX

Costa Mesa RC TR/RC TR RC

Crestline HC TP/RC

Fontana RC TP/RC TR RC HC EX/TP

Glendora RC TR/RC HC

Indio TP HC TP /EX

La Habra RC TR/RC RC

Lake Elsinore TP/RC TP/RC TP/RC LAX Hastings BK BK BK BK BK BK Long Beach ( North ) HC TR/RC TR/HC TR TR/RC EX/HC EX Los Angeles ( Main St. ) SO/RC SO/HC TR TR/RC TR/RC EX/HC EX Mira Loma ( Jurupa ) 2 TP/RC TP/RC TR/RC HC /CP Mira Loma ( Van Buren ) CP CP CP HC/CP CP Mission Viejo RC TR/RC TR/RC EX/RC

Norco TR/RC

Ontario Fire Station HC EX/RC Palm Springs TP/RC TP/RC TP TP/RC EX/TP

Pasadena TR/RC TR/HC TR/RC EX/RC

Perris TP TR

Pico Rivera # 2 RC HC HC EX/RC EX

Pomona RC RC HC

Redlands TP/RC TP/RC Rehrig (Exide) SO

Reseda RC TR/RC HC EX/RC

Riverside HC TR/RC EX/RC EX

Rubidoux TR/RC TR/RC TR TR/HC TR/HC EX/TR/HC EX

San Bernardino TR/RC TP/RC TR/HC TR/HC EX/TR EX

Santa Clarita RC TP/RC TP/HC RC EX/RC South Long Beach HC EX/SO EX Uddelholm ( Trojan Battery ) SO

Temecula 1

Upland RC TR/RC TR/RC EX Van Nuys Airport SO West Los Angeles RC TR/HC RC

1 Site to begin in 2010

2 Site to b e closed in 2010 or 201114

TABLE 4 Continuous PM 10 /PM 2.5 Monitoring Purpose, Objective, and Spatial Scales

MONITORING OBJECTIVE SPATIAL SCALE TYPE

HC

– High Concentrations MI

– Microscale TEOM

RC

– Representative Concentrations NS

– Neighborhood Scale BAM (NON

- FEM) BAM (FEM)

MONITORING PURPOSE

SO

– Source Impact RM

– Real

- Time Reporting/Modeling

TP

– Pollutant Transport SPM

– Special Purpose Monitoring

TR

– Trend Analysis

Location Continuous PM10 Continuous PM2.5

Type P urpose Objective Scale Type Purpose Objective Scale

Anaheim 1 BAM RM RC NS BAM/FEM SPM RC NS
Banning Airport BAM/NON

- FEM RM RC NS

Burbank 1 TEOM RM RC NS BAM/FEM SPM RC NS

Crestline BAM/NON

- FEM RM RC NS

Glendora BAM RM RC NS BAM/NON

- FEM RM RC NS

Indio TEOM RM HC NS

Lake Elsinore TEOM RM RC NS BAM/NON

- FEM RM RC NS
Long Beach ( North ) 1 BAM RM RC NS BAM/FEM SPM RC NS
Los Angeles ( Main St. ) 1 BAM RM RC NS BAM/FEM SPM HC NS

Mira Loma ( Jurupa ) TEOM RM HC NS

Mira Loma ( Van Buren ) 1 BA M RM HC NS BAM/FEM SPM HC NS
Palm Springs TEOM RM HC NS

Reseda BAM/NON

- FEM RM RC NS

Riverside BAM RM HC NS BAM/NON

- FEM RM HC NS

Rubidoux 1 TEOM RM HC NS BAM/FEM & NON

FEM SPM/RM HC NS

San Bernardino TEOM RM RC NS

Santa Clarita BAM/ NON

- FEM RM RC NS
South Long Beach 1 BAM/FEM SPM RC NS

Temecula 2 BAM/NON

- FEM RM RC NS

Upland BAM RM RC NS BAM/NON

- FEM RM RC NS

1 PM2.5 FEM BAM Samplers replaced NON

- FEM Samplers during FY 2008

- 2009 and designated as special purpose monitors

2 Site planned during Fiscal Year 2010

- 201115

TABLE 5 PM2.5 FRM Monitoring Stations Assigned Site Numbers

Location Site Code CARB No. AQS No. Start Date Schedule

Anaheim ANAH 30178 060590007 01/03/99 Daily

Azusa AZUS 70060 060370002 01/04/99 1

- i n

- 3
Big Bear BGBR 36001 060718001 02/08/99 1

- in

- 6

Burbank 1 BURK 70069 060371002 01/21/99 Daily
Compton COMP 70112 060371302 11/08 1

- in

- 3

Fontana FONT 36197 060712002 01/03/99 1

- in

- 3

Indio “A” INDI 33157 060652002 01/30/99 1

- in

- 3

Indio “B” INDI 3315 7 060652002 05/12/00 1

- in

- 6
Long Beach ( North ) LGBH 70072 060374002 01/03/99 Daily Los Angeles “A” ( Main St. ) CELA 70087 060371103 01/03/99 Daily Los Angeles “B” ( Main St. ) CELA 70087 060371103 01/06/99 1

- in

- 6
Mira Loma (Van Buren) MRLM 33165 06065800 5 11/09/05 Daily
Mission Viejo MSVJ 30002 060592022 06/15/99 1

- in

- 3

Ontario Fire Station ONFS 36025 060710025 01/03/99 1

- in

- 3
Palm Springs PLSP 33137 060655001 12/26/99 1

- in

- 3

Pasadena PASA 70088 060372005 03/04/99 1

- in

- 3

Pico Rivera #2 PICO 70185 060 371602 09/12/05 1

- in

- 3

Reseda RESE 70074 060371201 01/24/99 1

- in

- 3

Riverside RIVM 33146 060651003 01/06/99 1

- in

- 3

Rubidoux “A” RIVR 33144 060658001 01/03/99 Daily

Rubidoux “B” RIVR 33144 060658001 01/03/99 1

- in

- 6

San Bernardino SNBO 36203 060719004 01 /03/99 1

- in

- 3

South Long Beach SLGB 70110 060374004 06/20/03 Daily

1 Changed to daily on 04/16/09 for comparison to FEM BAM16

TABLE 6 PAMS Network

July 1 to September 30 October 1 to June 30

Site Type Date

Esta b lished as

PAMS Site / AQS ID# VOC C arbonyl VOC Carbonyl Additional Requir e ments

1 04/01/2004 LAX Hastings (r e placed Hawthorne) 8 x 3 hr samples every

3rd day and 1 x 24 hr sample every 6th day No Sampling 1 x 24 hr sample every 6th day No Sampling

2 06/01/1995 Azusa 8 x 3 hr samples ever y 3rd day and 1 x 24 hr

sa m ple every 6th day No Sampling 1 x 24 hr sample every 6th day No Sampling No/NOx required

2 07/01/1997 Burbank Continuous GC and 1 x 24 hr sample every 6th day 8 x 3 hr samples every day and 1 x 24 hr

sa m ple every 6th day 1 x 24 hr sample

every 6th day 1 x 24 hr sample

every 6th day

2 06/01/2009 Los Angeles (Main) 8 x 3 hr samples every 3rd day and 1 x 24 hr

sa m ple every 6th day 8 x 3 hr samples every

3rd day and 1 x 24 hr sample every 6th day 1 x 24 hr sample every 6th day 1 x 24 hr sample

every 6th day Trace level CO required

at one type 2 site.

2 08/01/2005 Pico Rivera #2 Continuous GC and 1 x 24 hr sample every 6th day 8 x 3 hr samples every day and 1 x 24 hr

sa m ple every 6th day 1 x 24 hr sample

every 6th day 1 x 24 hr sample

every 6th day

3 06/09/2009 Rubidoux 8 x 3 hr samples every 3rd day and 1 x 24 hr

sa m ple every 6th day No Sampling 1 x 24 hr sample every 6th day No Sampling NOy required

3 05/01/2001 Santa Clarita 8 x 3 hr samples every 3rd day and 1 x 24 hr

sa m ple every 6th day 8 x 3 hr samples every

3rd day and 1 x 24 hr sample every 6th day 1 x 24 hr sample every 6th day 1 x 24 hr sample

every 6th day

SITE TYPES : MONITORING REQUIREMENTS : REDUCED REQUIREMENTS : 1

– Upwind and background characterization site One type 1 or type 3 site required per area Speciated VOC only required at type 2 and one other (type 1 or 3)

2

– Maximum O3 precursor emissions impact site One type 2 site required per area Carbonyl only required in areas classified as serious

or above 8 hr zone

3

– Maximum O3 concentration site No type 4 required NO/NOx required only at type 2

4

– Extreme downwind monitoring site NOy required at one site per PAMS area (type 1 or 3)17

TABLE 7 Ambient Air Quality Standards181920

FIGURE 1 Distance of PM Samplers to Nearest Traffic Lane in M eters

Source: CFR 40 § 58 Appendix E21 

## II. SITE ASSESSMENTS

OVERVIEW
This section describes the process that was undertaken for assessing individual sites in the South Coast AQMD monitoring network. It describes criteria used to assess sites

, which include site history, security of future occupancy, infrastructure, monitoring objectives, probe s iting c riteria,

data uses

, and cost. The assessment criteria also include potential synergies that are co n sidered in assessing the i mportance of a monitoring site.



### SITE A SSESSMENT C RITERIA D ESCRIPTIONS

Site History/Longevity Many sites in the South Coast AQMD network h ave been in operation for more than 20 years. Establishing historical data trends over a period of time assists in determining the

effectiveness of control measures.

Security of Future Occup ancy Many of the sites in the South Coast AQMD network are established at properties that are leased on a monthly or annual basis. Many sites are located at municipal properties where continuance of the current agreement will not change in the foreseeable future. There are however, locations where property owner needs such as refusal to establish long term lease, expansion of facilities, remodeling, or increases in rent make security o f future occupancy uncertain.

Infrastructure

Consideration of the infr astructure at air monitoring locations is a crucial part of the site

asses s ment. The condition of the building, electrical capabilities, data communication capabilities, and space for expansion are evaluated.

Probe Criteria The earliest monitoring statio ns were established in the late 1950 ’ s and since that time

urban d e velopment and changes in land use, population

, and air quality trends have

affected moni toring objectives and the probe siting criteria so that air pollution data may no longer adequately r epresent the intended area. Requirements for probe siting criteria

includes an examin a tion of the horizontal and vertical probe placement

, spacing of the probe from obstructions

, spa c ing of the probe in relation to minor sources, and spacing of the probe from roadways based on the individual criteria pollutant spatial scale of representativeness a nd Average Daily Traffic (ADT).

Non

- NAA Q S Data Uses Besides NAAQS compliance status evaluation and progress demonstrations, data from South Coast AQMD air monito ring stations is used for real

- time public notification of air pollution events, air quality forecasting, and the analys i s and modeling for strategic plan development, including the prep a ration of the Air Quality Management Plan (AQMP). Due to the large p opulation in S outhern California and the complexity of the geography and meteorology, a relatively large number of air monitoring stations are needed to22

adequately describe air quality and meteorology in South Coast AQMD ’s jurisdiction.
As a whole, the So uth Coast AQMD air monitoring network successfully meets the needs for planning, public notification

, and forecasting purposes.

Public Notification Data from the criteria pollutants that are measured continuously are available to the public in near real t ime , through the South Coast AQMD , U.S. EPA AirNow, and California Air Resourced Board websites, as well as through the South Coast AQMD Interactive Voice Response (IVR) automated phone sy s tem. Warnings of current air pollution events that occur are trans mitted to the public via the South Coast AQMD website, fax, email, recorded phone messages

, and press releases.

The U.S. EPA Env i roFlash alert system is used to alert subscribers of measured unhealthy air quality by email, RSS feeds or Twitter alerts. At this time, air quality notifications are primarily driven by PM2.5 and summertime O3 measurements, although PM10 episodes can also occur occasionally during exceptional events (e.g., natural windblown dust events, wildfires, and fireworks displays). A ro bust real

- time network is needed to support the accurate mapping of data and transmittal of episodic health information for the large population and geographic diversity of the SCAB and the Coachella Valley.

Air Quality Forecasting South Coast AQMD provid es daily air quality forecasts to the public, predicting day

- in

- advance concentrations and Air Quality Index (AQI) values of O3 , PM2.5, PM10, CO

, and NO2 for 38 source

- receptor areas throughout South Coast AQMD ’s jurisdiction. The forecasts are di s seminat ed to the public through the South Coast AQMD and U.S. EPA AirNow websites, the South Coast AQMD IVR phone system, and through the news media, as well as by subscription via fax, email, RSS feeds

, and Twitter (using EnviroFlash). South Coast AQMD also

pro vides high wind/windblown dust forecasts for the Coachella Valley for South Coast AQMD Rule 403.1, agricultural and wildland prescribed fire burn for e casts and, starting in November 2010, residential wood burning forecasts. South Coast AQMD air quality fo recast tools utilize forecaster experience, empirical/statistical

models

, and prognostic grid mo d els. Current and historical air quality and meteorological data are critical to the forecasting process. The South Coast AQMD measurements are used to develo p the empirical models and to provide current inputs during daily forecast preparation. The monitoring data is also used to evaluate and refine the prognostic grid models.

Air Quality Planning South Coast AQMD measurements are important for the air quali ty planning process, including strategic plan development to demonstrate future year attainment of the NAAQS. Current levels and historic air quality trends are documented as a component of the AQMP and reasonable further progress analysis . Meteorologica l and air quality models are used to simulate representative past episodes or longer periods, as compared to measured air quality data throughout the region. Emi s sions are then be adjusted in the model23 for future years based on projected population, busin ess growth, infrastructure and

the effect of control measures to evaluate the efficacy of potential emissions control strategies. A relatively dense monitoring network of pollutants and their

pr e cursors is needed throughout the modeling domain to adequate ly evaluate the ability of the mo d els to simulate air quality.

Health Studies Support for air pollution research studies is prime objective in assessing the value

of an air mon i toring location. Air pollution data collected is used to supplement

data coll ected by researchers working on health effects assessments. Sites used as

p latforms for scientific studies involved with health or welfare impacts, measurement methods development, or used as collaborative e f forts with

researchers are considered here due to their important role in supporting the air quality management program

.

Environmental Justice (EJ) Following the South Coast AQMD Board’s EJ initiatives in October 1997, the South Coast AQMD has been a leader in identifying and addressing community

EJ c oncerns, pa r ticularly as raised by low income, ethnic minority communities who may be disproportionately impacted by localized emissions and mobile source pollutants. In support of the program, t o x ics monitoring and periodic health effects studies take pl ace at air monitoring locations throug h out the network. Support of these studies is taken into consideration while determining the value of an air monitoring location.

Cost Assessment of the cost to relocate a site is an important factor is determining t he value of a monitoring location. Cost assessment takes into account the availability of sampling locations in the area, as well as the cost of rent and the number of monitors at the sampling site.

Synergies Consideration of potential synergies between monitoring programs and external objectives are tak en into account while establishing the value of the monitoring location. Establishing s y nergies between monitoring programs such as NCore, PAMS, NATTS, Health Studies, and South Coast AQMD ’s EJ programs e nhance the value of the monitoring loc a tion. Synergies external to the air monitoring network that are taken into consideration while determining the value of the site include use of facilities by South Coast AQMD field i n spection personnel for office spa ce and data communications.



### INDIVIDUAL SITE ASSE SSMENTS

The current AQMD air monitoring network meets or exceeds U.S. EPA monitoring requirements

and satisfies multiple monitoring purposes. Over the last twenty years, population, sources of pollution, a mbient levels of pollution, and the surveillance air monitoring network have been

modified such that the o riginal monitoring objectives of each site may no longer apply . The24

effects of these factors

, as well as data and mon i toring needs

, are assessed by s ite. Measurements taken at each air monitoring site , AQS number

, and date o f inception are shown

in Table 1

. The p robe siting c riteria a ssessment is shown in T a ble 15

.

Anaheim The Anaheim site was established at its current location at 1630 Pampas Lane in August

2001 after movin g from 1010 Harbor Blvd. due to sale of the Orange County Agricultural Department facility where the site had resided since 1981 . We currently hold a 5 year

lease with the An a heim School District for our current monitoring locati on and do not anticipate any changes in the near future. The infrastructure of the facility requires attention. The current monitoring platform began as a temporary location, and therefore was not supported adequately. The monitoring pla t form needs to b e removed, and supported properly with a cement base. Concurrently, the co m pound in which the site is housed needs to be expanded and electrical wiring upgraded to a c commodate the necessary changes to meet probe siting criteria

. The site does not current ly meet 40 CFR § 58 Appendix E Probe Siting Criteria, specifically spacing from trees requirement and probe distance from traffic lane. Spacing from trees for all pollutants should be at least

10 m and distance from traffic land should be a minimum of 10 m and 15 m respectively for gaseous and particulate pollutants. Distances are shown in Table 15. Non

- NAA Q S

data uses include modeling and forecasting of daily pollution levels for public

i n formation. Synergies between air monitoring programs include spe ciated PM2.5 sampling, Radnet program
, EJ

, and regional toxics air monitoring studies. The cost to
relocate the site to meet probe siting criteria is high due to the number of i n struments at the site, cost of rent in the area, and length of service

.

ATSF (Exide) The ATSF site was established at its current location in January 1999 to monitor Pb source emissions from the Exide facility in the City of Commerce. We currently have an agreement with the owners of the property to allow air monitoring and do no t anticipate any changes in the near future. The infrastructure is adequate and probe siting criteria meets requirements for source impact siting. The cost to move the location is low

, however, the current site is the best available location.

Azusa

The Azusa site was established at its current location in January 1957 . We currently hold

a 5 year lease for our monitoring location and do not anticipate any changes in the near

future. The infrastructure meets the needs of the air monitoring network . The site is in compliance with 40 CFR § 58 Appendix E Probe Siting Criteria. Non

- NAAQS data uses include modeling and forecasting of daily pollution levels for public information. Synergies b e tween air monitoring programs include PAMS

, C ARB

, and administrati ve synergies include use of office space for Air Quality Inspectors. The cost to relocate the

site is high due to the number of instruments at the site, cost of rent in the area, and length of service.25

Banning Airport The Banning Airport site was estab lished at its current location during April 1997

, after moving from the Banning

- Alessandro air monitoring location . We hold a 4 year lease

with the airport for our monitoring location and do not anticipate any changes in the near

future. The infrastru c tu re of the facility meets the needs of the air monitoring network

. The site meet s 40 CFR § 58 Appendix E Probe Siting Criteria. Non

- NAAQS data uses

include mode l ing and forecasting of daily pollution levels for public information. Administrative sy nergi es include use of office space for Air Quality Inspectors. The cost

to relocate the site to meet probe siting criteria is high due to the number of instruments at the site, cost of rent in the area, and length of service.

Big Bear The Big Bear site was e stablished at its current location in February 1999 to assess PM2.5 wi n ter wood smoke . We currently have a 2 year agreement with airport management and do not a n ticipate any changes in the near future. The infrastructure is adequate and meets 40 CFR § 58 Appendix E Probe Siting Criteria. The cost t o move the location is low, and there have been no exceedances of the PM2.5 standard , however the cost to maintain the site is high due to the distant location.

Burbank

The Burbank site was established at it s c urrent location at 228 West Palm Avenue during

Oct o ber 1961 . We currently hold a 3 year lease with the owners of the monitoring location and do not anticipate any changes in the near future. The infrastructure of the facility is adequate . The site ho wever does not currently meet 40 CFR § 58 Appendix E Probe Siting Criteria, specifically spacing from traffic lane for O3 and NO2 are 6

. 2 meters short of requirement. Distances are shown in Table 15. Non

- NAAQS data uses include modeling and forecasting o f daily pollution levels for public information. Synergies between air monitoring programs include PAMS, BioWatch, Regional Toxics studies, and CARB Toxics monitoring. Administrative synergies include use of office space for Air Quality Inspectors . The cost to rel o cate the site to meet probe siting criteria will be higher than the current loc a tion due to the high cost of rent in the area and number

of monitors.

Closet World (Quemetco)

The Closet World site was established at its current location in Oct ober 2008 to monitor

Pb source emissions from the Quemetco facility in the City of Industry . We currently have an agreement with the owners of the property to allow us to sample and do not anticipate any changes in the near future. The infrastructure is adequate and probe siting criteria meets requirements for source impact siting. The cost to relocate is low due to a single instrument at the site.

Compton The Compton site was established at its current location at 700 North Bullis Road in January 2004 after moving from the Lynwood site due to inadequate site infrastructure

. We currently hold a 10 year lease with the City of Compton for our current monitoring location and do not anticipate any changes in the near future. The infrastructure of the26

site meets the needs of the air monito r ing network . The site meets requirements of 40 CFR § 58 Appendix E Probe Siting Criteria, spacing from roadways, trees, and

obstructions . Non

- NAAQS data uses include modeling and forecasting of daily pollution

levels for public information. Administr a tive synergies include use of office space for Air Quality Inspectors. The cost to relocate the site is high due to the number of

instruments at the site and cost of rent in the area.

Costa Mesa

The Costa Mesa site was est ablished at its current location in November 1989. We currently hold a 5 year lease with the owners for our current monitoring location and do not anticipate any changes in the near future. The site lacks adequate space to expand to include particulate s a m pling. The site meets requirements of 40 CFR § 58 Appendix E

Probe Si t ing Criteria, spacing from roadways, trees, and obstructions. Non

- NAAQS data uses include modeling and forecasting of daily pollution levels for public information.

Administrative s yne r gies include use of office space for Air Quality Inspectors. The cost of relocating the site is si g nificant ; however, finding a site that can accommodate particulate sampling will add value to the network.

Crestline

The Crestline site was established at its current location at Lake Gregory in October 1973. We currently hold a month to month contract for our current monitoring location

with the San Be r nardino County Regional Parks Department, but do not anticipate any changes in the near future. The infrastructure of the facility requires attention. The current monitoring platform is outdated and lacks sufficient space

. Money has been set aside for a new monitoring platform but basic infrastructure must be installed first. The

site does not current ly meet 40 CFR § 58 Appendix E Probe Siting Criteria, specifically spacing from trees requirement

. D istances are shown in Table 15. Non

- NAAQS data uses include modeling and forecasting of daily poll u tion levels for public information.

The cost to reloca te the site to meet probe siting criteria is high due to the number of instruments at the site, cost of rent, and length of service.

Fontana

The Fontana site was established at its current location at 14360 Arrow Highway during August 1981. We currently hold a month to month lease with San Bernardino County

Fire for the mon i toring location and do not anticipate any changes in the near future. The infrastructure meets the needs of the air monitoring network; however

, there is no room for further expansion

. The site is in compliance with 40 CFR § 58 Appendix E Probe Siting Criteria, howe v er, the adjacent property is a large dirt lot which contains vegetation which will cause siting problems in the coming years. Non

- NAAQS data uses include modeling and for ecasting of daily pollution levels for public information. Synergies between air monitoring programs include speciated PM2.5 sampling, Radnet

program, EJ

, and R egional T oxics A ir M on i toring S tudies. The cost to relocate the site to

meet p robe siting c rit eria is high due to the number of instruments at the site, cost of rent in the area, and length of service.27

Glendora The Glendora site was established at its current location at 840 E. Laurel during August 1980. We currently hold a month to month lease with the city of Glendora for our monitoring location and are concerned about the future stability of remaining at the location. The current monitoring platform is housed in a structure which requires

attention. The site was established by California Air Resources Board in a now outdated housing . The monitoring platform needs to be removed, and supported properly with a cement base. Concurrently, the compound in which the site is housed needs to be expanded and electrical wiring upgraded to accommodate the necessary changes to meet probe siting criteria . The site is in compliance with 40 CFR § 58 Appendix E Probe Siting Criteria ; however

, the area is surrounded by a vacant dirt lot which can have an impact on particulate readings

. D istances are shown i n Table 15. Non

- NAAQS data uses include modeling and forecasting of daily pollution levels for public inform a tion. Synergies between air monitoring programs include the BioWatch program, regional

toxics studies

, and regional health studies. The cost to relocate is high due to the number

of instr u ments at the site, cost of rent in the area, and length of service. Cost can be mitigated by cons o lidating the site with nearby air monitoring locations.

Indio

The Indio site was established at its current loc ation at 46

- 990 Jackson Street during January 1983. We currently hold a month to month lease with the city of Indio and do not anticipate any changes in the near future. The current monitoring platform is a

modular wood structure, which requires extensiv e maintenance

. M oney has been set aside for a new monitoring platform . The site is in compliance with 40 CFR § 58 Appendix E Probe Siting Criteria ; however

, the area is surrounded by a dirt lot occasionally used as parking which can have an impact on pa r ticulate readings

. D istances are shown in Table 15. Non

- NAAQS data uses include modeling and forecasting of daily pollution levels for public information. The cost to relocate the site

to meet probe siting criteria is high due to the number of instrumen ts at the site, cost of rent in the area, and length of service.

La Habra

The La Habra site was established at its current location at 621 West Lambert Road during August 19 60

. We currently hold a month to month lease with the city of La Habra

and do not anticipate any changes in the near future . The site lacks adequate space to expand to include part i culate sampling and the monitoring structure requires attention

. The site does not currently meet 40 CFR § 58 Appendix E Probe Siting Criteria, specifical ly spacing from trees requirement and probe distance from traffic lane. Spacing from trees for all pollutants should be at least 10 m and distance from traffic land should

be a minimum of 10 and 15 m r e spectively for gaseous and particulate pollutants.

D istances are shown in Table 15. Non

- NAAQS data uses include modeling and forecasting of daily pollution levels for public inform a tion. Synergies between air monitoring programs include speciated PM2.5 sampling, Radnet program, and regional

toxics air mon itoring studies. The cost to relocate the site to meet probe siting criteria is high due to the number of instruments at the site, cost of rent in the area, and length of

service. Although the cost is significant , finding a site which can accommodate28

par ticulate samplin g will add value to the network and costs can be mitigated by consolidation with an existing air monitoring location.

Lake Elsinore The Lake Elsinore site was established at its current location at 506 West Flint St. during

June 1987. We currently hold a 4 year lease with the City of Lake Elsinore for the monitoring loc a tion and do not anticipate any changes in the near future. The infrastructure meets the needs of the air monitoring network. The site is in compliance with 40 CFR § 58 Ap pendix E Probe Siting Criteria ; however, the adjacent property contains vegetation which will cause siting problems in the coming years. Non

- NAAQS data uses include modeling and forecasting of daily pollution levels for public information. Synergies betw een air monitoring pr o grams include regional health studies.

The cost to relocate the site to meet probe siting criteria is high due to the number of instruments at the site, cost of rent in the area, and length of service.

LAX Hastings The LAX Hastings site was established at its current location at 7201 W. Westchester Parkway during April 2004. The site was established to replace the Hawthorne air monitoring location located on the grounds of Anza Elementary S chool in Hawthorne,

which was established t o r e place the Lennox air monitoring location. We currently hold

a month to month lease with Los Angeles International Airport for the monitoring location and do not anticipate any changes in the near future. The infrastructure meets

the needs of the air monitoring network; however

, there is no room for further expansion within the current compound . The site is in compliance with 40 CFR § 58 Appendix E Probe Siting Criteria

. Non

- NAAQS data uses include modeling and forecasting of daily pollution levels f

or public information. Synergies b e tween air monitoring programs

include PAMS and regional toxics air monitoring studies. The cost to relocate the site to

meet probe siting criteria will be significant due to the number of samplers and the

current low co st lease

.

Long Beach (North) The North Long Beach site was established at its current location at 3648 N Long Beach

Blvd during October 1961. We currently hold a 4 year lease with the owners of the monitoring loc a tion and do not anticipate any changes in the near future. The infrastructure of the facility is adequate. The site however

, does not currently meet 40 CFR § 58 Appendix E Probe Siting Criteria, specifically spacing from traffic lane for O3

, CO

, NO2 , PM10, and Pb

. D istances are shown in Table 15. Non

- NAAQS data uses

i n clude modeling and forecasting of daily pollution levels for public information. Synergies between air monitoring programs include Speciated PM2.5

, Regional Health Studies, EJ

, Regional Toxics studies, and CARB Toxics monitoring . Administrative synergies i n clude use of office space for Air Quality Inspectors. The cost to relocate the

site to meet probe siting criteria is high due to the number of instruments at the site, cost of rent in the area, and length of service.29

Los A ngeles (Main Street)

The Los Angeles Main Street site was established at its current location at 1630 North

Main Street in September 1979. We currently hold a month to month lease with the Los Angeles D e partment of Water and Power ( LA DWP ) for our current monitoring location and do not anticipate any changes in the near future. The infrastructure of the facility requires attention. The current mo n itoring platform lacks adequate space and power

. Arrangements have been made with LADWP to update the space a nd power to meet the needs of the network during FY20 10

- 11. The site is currently in compliance with 40 CFR § 58 Appendix E Probe Siting Crit e ria

. Non

- NAAQS data uses include modeling and forecasting of daily pollution levels for public information. Syn ergies between air monitoring programs include speciated PM2.5 sampling, PAMS, STN, NATTS

, NCORE,

EJ , regional health studies, regional toxics studies

, and CARB Toxics monitoring

. The cost to relocate the site is high due to the number of instruments at t he site, cost of rent in the area, and length of service.

Mira Loma (Jurupa) The Mira Loma Jurupa site was established at its current location at 10551 Bellegrave during December 1993 by CARB as part of the Children’s Health Study . We currently

have a no cost agreement with the Jurupa Unified School District for our monito r ing location and are unsure about the future stability of remaining at the location. The current monitoring platform is housed in a structure which requires attention. The current

mon itoring platform began as a temporary location with no room for expansion and poor

electrical infr a structure

. The site does not meet 40 CFR § 58 Appendix E Probe Siting Criteria, specifically spacing from obstructions, which is detailed in Table 15

. Non

- NAAQS data uses include modeling and forecasting of daily pollution levels for public information. Synergies between air monitoring programs include regional health

studies. The cost to relocate the site will be low due to a site established nearby to

re place this site due to the poor infrastructure.

Mira Loma (Van Buren)

The Mira Loma Van Buren was established at its current location at 5130 Poinsettia Drive during November 2005 . This location served as a replacement for the Mira Loma Jurupa site due t o th e location’s poor instr u ment siting and infrastructure. We currently have a no cost agreement with the Jurupa Unified School District for our monitoring

location and do not anticipate any changes in the near future . The site is in compliance

with the requirements of 40 CFR § 58 Appendix E Probe Criteria

. Non

- NAAQS data uses include modeling and forecasting of daily poll u tion levels for public information. Synergies between air monitoring programs include regional health studies and regional

toxics s tudies.

Mission Viejo

The Mission Viejo site was established at its current location at 26081 Via Pera during

June 1999 . We currently hold a 5 year lease with the El Toro Water District for the monitoring loc a tion and do not anticipate any changes in th e near future. The infrastructure meets the needs of the air monitoring network; however

, there is no room for further expansion within the current compound. The site is in compliance with 4030

CFR § 58 Appendix E Probe Siting Criteria. Non

- NAAQS data use s include modeling and forecasting of daily pollution levels for public information. The cost to relocate the

site to meet probe siting criteria will be significant due to the number of samplers and the

current low cost lease.

Norco

The Norco site was es tablished at its current location on the grounds of the N aval S urface

W arfare C enter in December 19 80 to examine O3 and p articulates . We currently have a

5 year co n tract through 2014 and do not anti cipate any changes in the near future. The

infrastructur e of the facility meets the needs of particulate sampling, but there are no facilities for continuous analyzers. The site is in compliance with 40 CFR § 58 Appendix E Probe Siting Criteria. T he cost to maintain the site is high, with a technician traveli ng to the site to mai n tain a single instrument. Non

- NAAQS data uses include modeling and forecasting of daily poll u tion levels for public information. There are no synergies between air monitoring programs or use of office space by inspectors

. The cost to
relocate the site is low to a single instrument at the site . This cost can be further mitigated by consolidation with a nearby site.

Ontario Fire Station

The Ontario Fire Station site was established at its current location at 1408 E. Francis during J anuary 1999. We currently hold a 4 year lease with the City of Ontario for our current monitoring location and do not anticipate any changes in the near future. The

infrastructure of the facil i ty meets the needs of particulate sampling, but there are no facilities for continuous analyzers. The site does not currently meet 40 CFR § 58 Appendix E Probe Siting Cr i teria, specifically spacing from obstructions surrounding the

instrumentation

. D istances are shown in Table 15. Non

- NAAQS data uses include

mode ling and forecasting of daily pollution levels for public information. There are no synergies between air monitoring programs or use of office space by inspectors

. The cost to relocate the site is high due to the number of samplers but this can be mitiga ted by consolidation with a nearby site.

Palm Springs The Palm Springs site was established at its current location at 590 Racquet Club Road during April 1971 . We currently hold a 4 year lease with the City of Palm Springs for

our current mo n itoring loca tion and do not anticipate any changes in the near future. The infrastructure of the facility currently meets the needs of the monitoring network

, but

there is no room for future e x pansion . The site does not currently meet 40 CFR § 58 Appendix E Probe Si ting Criteria, specifically spacing from obstructions and pro be

distance from traffic lane

. D i s tances are shown in Table 15. Non

- NAAQS data uses include modeling and forecasting of daily pollution levels for public information. There

are no s ynergies be tween air monitoring programs or use of office space by inspectors

. The cost to relocate the site to meet probe siting criteria will be high due to number of analyzers and length of service.31

Pasadena

The Pasadena site was established at its current loc ation at 752 Wilson Ave during April

1982 . We currently hold a month to month lease with the California Institute of Technology for our current monitoring location and do not anticipate any changes in the

near future. The infrastru c ture of the facility r equires attention. The current monitoring platform is housed in a structure, which is outdated . M oney has been set aside for a new monitoring platform but basic infrastru c ture is lacking and the compound in which the site is housed needs to be expanded

. The site does not currently meet 40 CFR § 58 Appendix E Probe Siting Criteria, specif i cally spacing from trees requirement . S pacing from trees for all pollutants should be at least 10 m . D istances are shown in Table 15.

Non

- NAAQS data uses include mode ling and forecasting of daily pollution levels for public information. There are no synergies between air monitoring programs or use of office space by inspectors. The cost to relocate the site to meet probe siting criteria will be higher due to the numb er of samplers , length of service

, and cost of space in the area.

Perris The Perris site was established at its current location at 237 North D Street during May 1973. We currently hold a 2 year lease for our current monitoring location with

Riverside County and do not anticipate any changes in the near future. The current monitoring platform is housed in a structure which requires attention. The site does not currently meet 40 CFR § 58 Appendix E Probe Siting Criteria, specifically spacing from

obstr uctions

. D istances are shown in Table 15. Non

- NAAQS data uses include modeling and forecasting of daily pollution levels for public information. There are no synergies between air monitoring programs or use of office space by inspectors. The cost

to r e lo cate the site to meet probe siting criteria will be higher than the current location,

which is at no cost due to its location on a public facility.

Pico Rivera #2

The Pico Rivera #2 site was established at its current location at 4144 San Gabriel River

Par k way in September 2005 after moving from 3713

- B San Gabriel River Parkway due

to influences from surrounding facilities. We currently hold a 2 year lease with the Whittier Utility Authority and do not anticipate any changes in the near future. The

inf rastructure of the facility meets the needs of the air monitoring network. The site is in compliance with 40 CFR § 58 Appendix E Probe Siting Criteria . D istances are shown in

Table 15. Non

- NAAQS data uses include modeling and forecasting of daily pollut ion levels for public information. Synergies between air monitoring programs include PAMS and Regional Toxics studies. The cost to rel o cate the site is high due to the number of samplers, length of service and cost of space in the area.

Pomona

The Pomon a Fire Station site was established at its current location at 924 Garey Ave in June 1965 to investigate CO emissions from motor vehicles . We currently hold a 3 year lease and do not anticipate any changes in the near future. The infrastructure of the

fa cility r e quires attention. The current monitoring building is outdated and does not allow for particulate sampling. The site does not currently meet 40 CFR § 58 Appendix

E Probe Siting Criteria, specifically spacing from roadway for O3 and NO2 . D istance s32

are shown in Table 15. Non

- NAAQS data uses include modeling and forecasting of daily pollution levels for public information. There are no synergies between air monitoring

programs ; however, calibration and repair technicians use space as a workshop. The cost to relocate the site is high due to the number of samplers and length of service, but this can be mitigated by consolidation with a nearby sites.

Redlands The Redlands site was established at its current location at 500 Deerborn Ave during Septem ber 1986. We currently hold a month to month lease with the City of Redlands and do not anticipate any changes in the near future. The infrastructure of the facility requires attention. The current monitoring platform is housed in a structure which is

o utdated . M oney has been set aside for a new monitoring platform

, but basic infrastructure is lacking and the compound in which the site is housed needs to be expanded. The site does not currently meet 40 CFR § 58 Appendix E Probe Siting Criteria, specifi cally spacing from trees requirement . S pacing from trees for all pollutants should be at least 10 m . D istances are shown in Table 15. Non

- NAAQS data uses include modeling and forecasting of daily pollution levels for public inform a tion. There are no sy nergies between air monitoring programs or use of office space . The cost

to relocate the site to meet probe siting criteria will be higher than the cu rrent location which is on a public facility.

Rehrig (Exide) The Rehrig site was established at 4010 E. 26th Street in the City of Vernon during October 2007 to monitor Pb source emissions from the Exide facility in the City of

Vernon . We currently have an agreement with the owners of the property to allow us to sample and do not anticipate any changes in t he near future. The infra structure is adequate and probe si ting criteria meets requirements for source impact siting.

Reseda The Reseda site was established at its current location at 18330 Gault Street during

March 1965 . We currently hold a 5 year le ase with the owners of the monitoring location and do not anticipate any changes in the near future. The infrastructure of the facility is adequate. The site however does not currently meet 40 CFR § 58 Appendix E Probe Siting Criteria, specifically spaci ng from traffic lane for O3 and NO2 . D istances are

shown in Table 15. Non

- NAAQS data uses include modeling and forecasting of daily pollution levels for public inform a tion. There are no synergies between air monitoring

programs ; however, a dministrative synergies include use of office space for Air Quality Inspectors. The cost to relocate the site to meet probe siting criteria will be higher than

the current location due to th e high cost of rent in the area, number of monitors

, and length of service.

Ri verside (Magnolia) The Riverside site was established at its current location at 7002 Magnolia Avenue during Oct o ber 1972 by the CARB to investigate CO emissions from motor vehicles . We currently have a 3 year lease with the owners of the facility for our monito r ing location

and do not expect any changes in the near future

. The monitoring platform meets the33

needs of the current monitoring program ; however

, there is no room for further expansion

. The site does not meet 40 CFR § 58 Appendix E Probe Siting Criteria,

sp e cifically spacing from roadway which is detailed in Table 15. Non

- NAAQS data uses include modeling and forecasting of daily pollution levels for public information. Synergies between air monitoring programs include health studies research;

a dministrative synergies include use of o f fice space for Air Quality Inspectors. The cost

to relocate the site to meet probe siting criteria will be higher than the current location due to the high cost of rent in the area, number of monitors

, and length o f service.

Rubidoux

The Rubidoux site was established at its current location at 5888 Mission Boulevard during September 1972. We currently hold a 3 year lease with Southern California

Edison for our cu rrent monitoring location and do not anticipate any changes in the near future. The infrastructure of the facility has been recently updated and meets the need of monitoring network. The site is currently in compliance with 40 CFR § 58 Appendix E

Probe Siting Crit e ria. Non

- NAAQS data uses include modelin g and forecasting of daily pollution levels for public information. Synergies between air monitoring programs include speciated PM2.5 sampling, PAMS, STN, NATTS, NCORE, CARB Toxics monitoring , and regional toxics air monitoring studies. The cost to reloc ate the site to

meet probe siting criteria will be higher than the current location due to the number of monitors, length of service, and cost of rent in the area.

San Bernardino

The San Bernardino site was established at its current location at 24302 Eas t 4th Street during May 1986. We currently hold a 3 year lease with the City of San Bernardino Unified School District and do not anticipate any changes in the near future. The infrastructure of the facility requires attention. The current monitoring pl atform is

housed in a structure which is outdated . M oney has been set aside for a new monitoring platform

, but basic infrastructure is lacking and the compound in which the site is housed needs to be expanded. The site is in compliance with 40 CFR § 58 A ppendix E Probe Siting Criteria with criteria shown in Table 15. Non

- NAAQS data uses include modeling and forecasting of daily pollution levels for public information. Synergies between air monitoring programs include EJ and regional toxics studies. The cost to relocate the site

to meet probe siting criteria will be higher than the current location due to the number of instruments, length of service

, and cost of rent in the area.

Santa Clarita

The Santa Clarita site was established at its current loca tion at 22224 Placerita Canyon

Road du r ing May 200 1 after moving from 24875 San Fernando Road at the request of Los Angeles County Fire Station #73. We currently have an agreement with Los Angeles County for space and do not anticipate any changes in the near future. The infrastructure of the facility meets the needs of the air monitoring network. The site is in compliance with 40 CFR § 58 Appendix E Probe Siting Criteria . D istances are shown in Table 15.

Non

- NAAQS data uses include modeling and foreca sting of daily pollution levels for public information. Synergies between air monitoring programs include PAMS and34

Regional Toxics studies. The cost to rel o cate the site is high due to the number of samplers, length of service

, and cost of space in the a rea.

South Long Beach The South Long Beach site was established at its current location at 1305 E Pacific Coast Hig h way during June 2003 to monitor particulate influence from port activities. We currently have an agreement to monitor with the Long Beac h City College for our current monitoring location and do not anticipate any changes in the near future. The infrastructure of the facility meets the needs of particulate sampling, but there are no facilities for continuous analyzers and no room for expan sion. The site does not currently meet 40 CFR § 58 Appendix E Probe Siting Criteria, specifically spacing from obstructions surrounding the instrumentation . D i s tances are shown in Table 15. Non

NAAQS data uses include modeling and forecasting of daily p ollution levels for public information. There are no synergies between air monitoring programs or use of office space by inspectors. The cost to relocate the site is low due to the number of samplers

and this can be further mitigated by consolidation wit h a nearby site.

Temecula

The Temecula site was established at its current location at Lake Skinner MWD Facilities during July 2010. We currently hold an open ended lease with MWD for our current monitoring loc a tion and do not anticipate any changes in t he near future. The infrastructure meets the needs of the monitoring network and is in compliance with 40 CFR § 58 Appendix E Probe Siting Criteria

. Non

- NAAQS data uses include modeling and forecasting of daily poll u tion levels for public information. T here are no synergies between air monitoring programs and the site is restricted to operations personnel only

.

Uddelholm

The Uddelholm site was established at 9313 Santa Fe Springs Road in the City of Santa Fe Springs during October 1992 to monitor Pb source emissions from the Trojan Battery facility. We currently have an agreement with the owners of the property to allow us to sample and do not anticipate any changes in the near future. The infrastructure is adequate and probe siting criteria meets r equirements for source impact siting

.

Upland The Upland site was established at its current location at 1350 San Bernardino Road during March 1973. We currently hold a month to month lease with the Upland Cascade Mobile Home Park for our monitoring locat ion and do not anticipate any changes in the

near future. The mon i toring platform is adequate for the current location and t he site is in compliance with 40 CFR § 58 Appendix E Probe Siting Criteria. Non

- NAAQS data uses

include mo d eling and forecasting o f daily pollution levels for public information. Synergies between air monitoring programs include the regional health studies. The cost

to relocate the site will be high d ue to potential higher rent, number of samplers, and length of service . This can be mit i gated by consolidating the site with nearby air monitoring locations.35

Van Nuys Airport

The Van Nuys Airport site was established at 16345 Raymer during January 20 10 to
monitor Pb source emissions from the Van Nuys Airport . We currently have an

ag reement with the owners of the property to allow us to sample and do not anticipate any changes in the near future. The infrastructure is adequate and probe siting criteria meets requirements for source impact si t ing

.

West Los Angeles The West Los Angele s site was established at its current location at Wilshire and

Sawtelle Bo u levards on the grounds of the Veterans Administration Hospital during May 1984. We currently have an agreement with the VA A dministration to monitor and do not anticipate any chang es in the near future. The infrastructure of the facility requires attention. The current monitoring pla t form is housed in a structure which is outdated

. T he site is in compliance with 40 CFR § 58 A p pendix E Probe Siting Criteria with

criteria shown in Table 15. Non

- NAAQS data uses include modeling and forecasting of daily pollution levels for public inform a tion. There are no synergies between air monitoring programs or use of office space. The cost to relocate the site to meet probe siting criteria w ill be higher than the cu r rent location due to the number of instruments, length of service

, and cost of rent in the area.36 1 Welding shop

2 Propeller airplane exhaust TABLE 15 Probe Siting

Metric Horizontal

and vertical placement Spacing

from

minor

sources Spacing from

obstructio ns Spacing from trees Probe distance from traffic lane (m) ADT

Volume Probe

m a terial and sample

residence

time

Station Pollutant Actual Required Actual Required

Anaheim O3 1 None None 6 >10 7.5 >10 <500 7.4

CO 1 None None 6 >10 7.5 >10 <500 6.4

NO2 1 None None 6 >10 7.5 >10 <500 7.5

PM10 2 None None 11 >10 10.5 >15 <500 NA

PM2.5 1 None None 8 >10 10 >15 <500 NA

Azusa O3 1 26 1 None 23 >10 14.5 >10 <500 7.9

CO 1 26 1 None 23 >10 14.5 >10 <500 6.7

NO2 1 26 1 None 23 >10 14.5 >10 <500 8.5

PM10 2 26 1 None 23 >10 18.5 >15 <500 NA

PM2.5 1 26 1 None 23 >10 15.8 >15 <500 NA

Banning O3 1 60 2 47 None 80 >20 <2000 8.2

NO2 1 60 2 47 None 80 >20 <2000 9.1

PM10 2 60 2 47 None 80 >15 <2000 NA

Big Bear PM2.5 1 None 32 36 >10 114 >15 287 6 NA

Burbank O3 1 None None 18 >10 13.8 >20 <2000 6.5

CO 1 None None 18 >10 13.8 > 1 0 <2000 6.3

NO2 1 None None 18 >10 13.8 >20 <2000 7.8

SO2 1 None None 18 >10 13.8 NA <2000 7.9

PM10 2 None None 19 >10 13.8 >15 <2000 NA

PM2.5 1 None None 20 >10 13.8 >15 <2000 NA

Compton O3 1 None None 16 >10 16.36 >10 <1000 7.6

CO 1 None None 16 >10 16.36 >10 <1000 8.7

NO2 1 None None 16 >10 16.36 >10 <1000 8.2

PM2.5 1 None None 13 >10 21 >15 <1000 NA

Pb 2 None None 17 >10 23 >15 <1000 NA

Costa

M e sa O3 1 None None 18 >10 34 >20 <2000 6.7

CO 1 None None 18 >10 34 >1 0 <2000 7.4

NO2 1 None None 18 >10 34 >20 <2000 8.8

SO2 1 None None 18 >10 34 NA <2000 9.5

Crestline O3 1 None None 9 >10 55 >20 <8000 10

PM10 2 None None 8 >10 55 >15 <8000 NA

PM2.5 2 None None 7 >10 55 >15 <8000 NA37

TABLE 15 (cont) Probe Siting

Metric Horizontal

and vertical placement Spacing from

minor sources Spacing from

obstructions Spacing from

trees Probe distance

from traffic lane (m) ADT

Tra f fic

Volume Probe

mater i al and sample

residence

time

Station Pollutant Actual Required Actual Required

Fontana O3 1 9 3,4 None 19 >10 92 >30 12500 5.5

CO 1 9 3,4 None 19 >10 92 >25 12500 5.1

NO2 1 9 3,4 None 19 >10 92 >30 1 2500 6.0

SO2 1 9 3,4 None 19 >10 92 NA 12500 6.5

PM10 2 9 3,4 None 14 >10 86 >15 12500 NA

PM2.5 1 9 3,4 None 16 >10 86 >15 12500 NA

Glendora O3 1 None None 16 >10 121 >20 1834 7.6

CO 1 None None 16 >10 121 >10 1834 7.0

NO2 1 None None 16 >10 121 >20 1834 7.8

PM10 2 6 3 None 16 >10 121 >15 1834 NA

PM2.5 1 6 3 None 16 >10 121 >15 1834 NA

Indio O3 1 6 3 60 None 88 >40 16528 12.5

PM10 2 6 3 60 None 88 >17 16528 NA

PM2.5 1 6 3 60 None 88 >17 16528 NA

La Habra O3 1 28 5 None 3 >10 40 >100 662 00 7.5

CO 1 28 5 None 3 >10 40 >150 66200 6.1

NO2 1 28 5 None 3 >10 40 >100 66200 7.4

Lake

Els i nore O3 1 None None 17 >10 50 >20 <2000 5.1

CO 1 None None 17 >10 50 >10 <2000 5.1

NO2 1 None None 17 >10 50 >20 <2000 5.7

PM10 2 None None 10 >10 50 >15 <2000 NA

PM2.5 1 None None 10 >10 50 >15 <2000 NA

LAX

Has t ings O3 1 600 6 None 20 >10 85 >20 <2000 6.1

CO 1 600 6 None 20 >10 85 >10 <2000 6.5

NO2 1 600 6 None 20 >10 85 >20 <2000 6.8

PM10 2 600 6 None 16 >10 92 >15 <2000 NA

Pb 2 600 6 None 16 >10 92 >15 <2000 NA

3 Unpaved parking

4 Diesel nearby

5 Refueling station nearby

6 Airport runway nearby38 7 Fire training facility TABLE 15 (cont) Probe Siting

Metric Horizontal

and vertical placement Spacing from

minor sources Spacing from

obstr uctions Spacing from trees Probe distance

from traffic lane (m) ADT

Traffic

Volume Probe

m a terial and sample

res i dence

time

Station Pollutant Actual Required Actual Required
Long Beach (North) O3 1 None 5 6 >10 8 >40 19900 6.9

CO (μs) 1 None 5 6 >10 8 2

- 10 19900 6.1

NO2 1 None 5 6 >10 8 >40 19900 8.4

SO2 1 None 5 6 >10 8 NA 19900 8.9

PM10 2 None 5 4 >10 8 >20 19900 NA

PM2.5 1 None 11 None 55 >20 19900 NA

Pb (μs) 2 None 5 4 >10 10 2

- 10 19900 NA

Los Angeles (Main St.) O3 1 45 30 None 71 >40 15276 7.1

CO 1 45 30 None 71 >45 15276 7.2

NO2 1 45 30 None 71 >40 15276 7.6

SO2 1 45 30 None 71 NA 15276 9.5

PM10 2 27 52 None 51 >15 15276 NA

PM2.5 1 27 52 None 51 >15 15276 NA

Pb 2 27 52 None 51 >15 15276 NA

Mira Loma (Jurupa) O3 1 None 2 None 165 >60 25717 4.5

CO 1 None 2 None 165 >80 25717 4.8

NO2 1 None 2 None 165 >60 25717 6.1

PM10 2 None 2 None 165 >25 25717 NA

Mira Loma (Van Buren) O3 1 None None 36 >10 14 >10 <1000 6.7

CO 1 None None 36 >10 14 >10 <1000 5.9

NO2 1 N one None 36 >10 14 >10 <1000 7.0

PM10 2 None None 40 >10 15 >15 <1000 NA

PM2.5 2 None None 40 >10 15 >15 <1000 NA

Mission Viejo O3 1 None None None 138 >20 <2000 11.4

CO 1 None None None 138 >10 <2000 11.1

PM10 2 None None None 175 >15 <2000 NA

PM2.5 1 None None None 175 >15 <2000 NA

Norco PM10 2 None None 29 >10 25 >15 <500 NA

Ontario (Fire

Station) PM10 2 96 7 7 18 >10 43 >15 <2000 NA

PM2.5 1 96 7 7 20 >10 43 >15 <2000 NA39 3 Unpaved parking

8 Print shop TABLE 15 (cont) Probe Siting

Metric Horizontal

and vertical pla cement Spacing from

minor sources Spacing from

obstructions Spacing from trees Probe distance

from traffic lane (m) ADT

Traffic

Volume Probe

m a terial and sample

res i dence

time

Station Pollutant Actual Required Actual Required

Palm Springs O3 1 None None 22 >10 17 >20 <5000 9.3

CO 1 None None 22 >10 17 >10 <5000 8.3

NO2 1 None None 22 >10 17 >20 <5000 9.5

PM10 2 None 3 19 >10 20 >15 <5000 NA

PM2.5 1 None 3 19 >10 13 >15 <5000 NA

Pasadena O3 1 None None 6 >10 66 >20 <5000 6.7

CO 1 None None 6 >10 66 >10 <5000 6.1

NO2 1 None None 6 >10 66 >20 <5000 6.7

PM2.5 1 None None 6 >10 70 >15 <5000 NA

Perris O3 1 None 7 30 >10 74 >60 39500 7.4

PM 10 2 None 7 30 >10 74 >40 39500 NA

Pico Rivera O3 1 9 3 None 30 >10 41 >40 <2000 0 6.8

CO 1 9 3 None 30 >10 41 >45 <20000 6.7

NO2 1 4 3 None 30 >10 41 >40 <20000 6.5

PM2.5 1 4 3 None 27 >10 35 >20 <20000 NA

Pb/SO4 2 4 3 None 27 >10 35 >20 <20000 NA

Pomona O3 1 None None None 7 >60 25000 7.4

CO (μs) 1 None None None 7 2

- 10 25000 7.0

NO2 1 None None None 7 >60 25000 8.2

Redlands O3 1 2 3 None 8 >10 26 >20 4709 17.5

PM10 2 2 3 None 10 >10 26 >15 4709 NA

Reseda O3 1 10 10 None 14 >10 16 >20 <2000 6.7

CO 1 10 10 None 14 >10 16 >10 <2000 6.0

NO2 1 10 10 Non e 14 >10 16 >20 <2000 7.8

PM2.5 1 10 10 None 14 >10 19 >15 <2000 NA

Riverside CO (μs) 1 None None 15 >10 27 2

- 10 40,000 11.4

NO2 1 None None 15 >10 27 >60 40,000 12.9

PM2.5 1 None None 15 >10 28 >40 40,000 NA

Pb/SO4 (μs) 2 None None 15 >10 28 2

- 10 40,000 NA40

TABLE 15 (cont) Probe Siting

Metric Horizontal

and vertical placement Spacing from

minor sources Spacing from

obstructions Spacing from

trees (m) Probe distance

from traffic lane (m) ADT

Tra f fic

Volume P robe material

and sample

residence time

Station Pollutant Actual Required Actual Required

Rubidoux O3 1 None 38 10 >10 119 >40 <20,000 4.7

CO 1 None 38 10 >10 119 >45 <20,000 5.6

NO2 1 None 38 10 >10 119 >40 <20,000 7.6

SO2 1 None 38 10 > 10 119 NA <20,000 7.5

PM10 2 None 18 10 >10 119 >2 0 <20,000 NA

PM2.5 1 None 20 10 >10 119 >2 0 <20,000 NA

Pb/SO4 2 None 18 10 >10 119 >2 0 <20,000 NA

San

Bernard i no O3 1 None None 14 >10 23 >20 <2500 7.9

CO 1 None None 14 >10 23 >10 <2500 7.4

NO2 1 None None 14 >10 23 >20 <2500 8.7

PM10 2 None None 19 >10 16 >15 <2500 NA

PM2.5 1 None None 19 >10 16 >15 <2500 NA

Pb 2 None None 19 >10 16 >15 <2500 NA

Santa Clarita O3 1 None None 30 >10 91 >20 <5000 6.6

CO 1 None None 30 >10 91 >10 <5000 6.0

NO2 1 None None 30 >10 91 >20 <5000 6.5

PM10 2 None None 30 >10 91 >15 <5000 NA

PM2.5 1 None None 30 >10 91 >15 <5000 NA

Long Beach (South) PM10 2 None 20 None 86 >15 <10000 NA

PM2.5 1 None 20 None 86 >15 <10000 NA

Pb/SO4 2 None 20 None 86 >15 < 10000 NA

Temecula O3 1 450 1 0 30 9 60 >10 1056 >20 6500 TBD

PM10 2 450 10 30 9 60 >10 1056 >15 6500 TBD
Upland O3 1 None None 19 >10 80 >20 <10000 9.5

CO 1 None None 19 >10 80 >10 <10000 8.4

NO2 1 None None 19 >10 80 >20 <10000 8.7

PM10 2 None No ne 12 >10 80 >15 <10000 NA

PM2.5 1 None None 12 >10 80 >15 <10000 NA

Pb/SO4 2 None None 12 >10 80 >15 <10000 NA

West Los Angeles O3 1 None None 45 >10 23 >20 <10000 7.5

CO 1 None None 45 >10 23 >10 <10000 6.9

NO2 1 None None 45 >10 23 >20 <10000 7 .9

9 Microwave tower

10 Water treatment facility41424344 

## III. NETWORK ASSESSM ENT

OVERVIEW
The current AQMD pollutant monitoring networks meet or exceed U.S. EPA monitoring requirements and satisfy multiple monitoring purp oses. This section describes the process for assessing individual pollutant networks and monitoring programs in the South Coast AQMD monitoring network. The criteria for assessing the networks include the examination of overall network monitoring objecti ves, the spatial scales of representativeness, the minimum number of

monitors r e quired by regulation, and correlation analysis to determine redundancy or gaps within

each network.



### NETWORK ASSESSMENT C RITERIA DESCRIPTIONS

The criteria used for network asse ssment are described below. They include an assessment of monitoring objectives and spatial scales relative to 40 CFR § 58 Appendix D criteria. Another criteria was a correlation analysis using the provided U.S. EPA tools to identify redundant sites

or g eographical areas which may need additional sites within a monitoring network. Finally, networks were evaluated against the regulatory requirements for the minimum number of monitors using the latest census data available.

Monitoring Objectives

Over the last twenty years, population, sources of pollution, ambient levels of pollution,

and the South Coast AQMD air monitoring network have been modified. A periodic reassessment of monitoring objectives will help ensure that the current network design

meets t he original and any new monitoring objectives.

Ambient air monitoring network design is specified, at a minimum, by the U.S. EPA and includes monitoring objectives and general criteria as outlined in 40 CFR § 58 Appendix

D . Each pollutant measured at e ach air monitoring site is related to a specific monitoring objective. Depending on pollutant, air monitoring networks are designed to meet all or a subset of the following objectives:

 Highest concentrations expected to occur in the geographical area cove red by the

ne t work.

 Representative concentrations in areas of high population density in the geographical area covered by the network.

 Impact of significant sources or source categories of pollution such as refineries

or sp e cific area sources such as r esidential fuel combustion.

 Background concentration levels, usually located upwind of the air monitoring

network.

 Regional transport of pollution to areas outside of the monitoring network usually

l o cated downwind of the air monitoring network.

 The last type of site required measures air pollution impacts on visibility, vegetation damage

, or other welfare based impacts.45

Spatial Scale of Representativeness Each monitoring objective or site type is also related to a specific spatial scale of

repres entativeness as shown in Table 8. The goal in deciding on a location for a monitor is to correctly match the spatial scale of representativeness with the monitoring objective for the site being established. Spatial scale of representativeness is the phys ical dimension of the air parcel being represented by the air monitoring l o cation. Spatial

scales are defined as:

 Microscale

– represents concentrations in an area ranging from several meters to

100 m.

 Middle scale

– represents concentr ations in an area from 100 m to .5 kilometers.

 Neighborhood scale

– represents concentrations in an area that has uniform land

use and is .5 kilometers to 4.0 kilometers.

 Urban scale

– represents concentrations in an area the size of a city, from 4 to 50

kilom e ters in size. Influence from sources of pollution may prevent homogenous representation of a pollutant on an urban scale.

 Regional scale

– represents concentrations in a homogenous geographical area without large sources of pollution, usually tens to hundreds of kilom eters in size.

Correlation Analysis The U.S. EPA provided tools to assist in the network assessment process. The Correlation Matrix Analysis shows the correlation, relative difference, and distance between pairs of sites within a Core Based Statistical A rea (CBSA) or a region. During

the static analysis , each CBSA displays a grap h ical matrix for O3, PM2.5 reference

, and equivalent methods and continuous particulate sites. The shape of ellipses represents the Pearson squared correlation between sites wit h circles representing zero correlation and a straight diagonal line representing a perfect correlation. The correlation between two sites quantitatively describes the degree of relatedness between the me a surements made at two sites. The correlation, how ever, may indicate whether a pair of sites is related, but it does not indicate if one site consistently measures pollutant concentrations at levels substantially higher or lower than the other. For this purpose, the color of the ellipses represents the a verage relative difference between sites where the daily relative

difference is defined as:

Where s 1 and s 2 represent the concentrations at sites one and two in the pairing, abs is

the absolute difference between the two sites and avg is the average of the two site concentrations. The average relative difference between the two sites is an indicator of the overall measurement similarity between the two sites. Site pairs with a lower average

relative difference are more similar to each other than pairs with a larger difference. The

distance between the sites infl u ences both the correlation and the relative difference between sites. Usually sites with a larger distance between them will generally be more poorly correlated and have large differences in the corresponding pollutant46

concentrations. The distance between site pairs in the correlation matrix graphic is displayed in kilometers in the middle of each ellipse.

The purpose of this analysis tool is to provide a means of ident ifying potential redundant sites that could be removed. Potentially redundant sites exhibit fairly high correlations of

0.8 consi s tently across all of their pairings and have low average relative difference, despite the distance between it and other sites . Usually, it is expected that correlation between sites will decrease as distance increases. However, for a regional air pollutant such as O3, sites in the same air shed can have very similar conce n trations and be highly correlated. More unique sites w ill tend to exhibit the opposite characteristics. They will not be very well correlated with other sites and their relative difference would be higher

than other site

- to

- site pairs.

Note that results from such a correlation analysis are just one criteria in assessing the

value of sites within a network. Other site

- specific or network design factors, such as health studies, EJ, inter

- program synergies, long

- term trends, and logistical constraints may add value to a site even if the measured concentrations are similar to other nearby

sites.

Minimum number of monitors As a general requirement, the U.S. EPA specifies the minimum numbers of sites required in a criteria pollutant network based on the latest census population data. For instance,

the minimum num ber of O3 sites required is based upon the MSA population and the

most recent 3

- year design value as shown in Table 9. These are minimum requirements and the total number of sites necessary to adequately satisfy all monitoring objectives may be higher. A s of 2009, there were no minimum requirements for the number of CO, NO2, and SO2 monitoring sites in an air monitoring network. More recent minimum requirements for NO2 and SO2 are not considered in this assessment. Discontinuing operations within existi ng monitoring networks, even if not required by regulation, is usually subject to U.S. EPA Regional Administrator approval. One minimum requirement for the number of Pb sites is based upon estimated source emissions. A site

must be located at maximum do wnwind concentration for each source that exceeds 1.0

- tons/year Pb emissions within the boundaries of the air monitoring network. Another minimum monitoring requirement for Pb is based on population. The number of PM10

sites r e quired is based upon MSA po pulation data and design values as shown in Table

10. The number of PM2.5 sites r e quired is based upon MSA population data and measured concentrations as shown in Table 11. The final number of sites required may be more than the regulatory minimums depen dent upon U.S. EPA Regional Approval of

Annual Network Plans.

The South Coast AQMD jurisdictional boundary encompasses two MSA’s as defined by the U.S. Office of Management and Budget and the U.S. Census Bureau. The Los Angeles

- Long Beach

- Santa Ana MSA (Code 31100) had a population of 12,365,627 based on the year 2000 U.S. Census. The Riverside

- San Bernardino

- Ontario MSA (Code 40140) had a population of 3,254,821 in 2000. The minimum number of monitors for each pollutant is based on MSA population and measured concentrations as described in 40 CFR § 58 Appendix D. The South Coast AQMD network exceeds the minimum monitoring requirements for all criteria pollutants.47



### P OLLUTANT NETWORK ASSESSMENTS

Ozone (O3) O3 is formed when the precursor gases VOC and NOx react in the atmosphere with sunlight. Emissions from VOC and NOx sources are frequently trapped in the South Coast Basin by the surrounding mountains and a persistent inversion layer. This leads to high ozone values, especially during the summer an d early fall months.

Regulatory Requirement Local agencies must operate O3 monitoring sites at various locations depending upon population and O3 design values relative to the NAAQS. Ambient air quality standards for O3 have been set by both the State an d Federal governments and continue to be made more stringent. The current ambient air quality standards for O3 are included in Table 7. To assess compliance with Federal and State standards, South Coast AQMD operates 30 sites with O3 measurements as

part of the Air Monitoring Network. Figure 2 shows the spatial distribution of

these sites.

Monitoring Objective The majority of the O3 monitoring network sites have been designated as population exposure monitoring locations as depicted in Table 18. Sites downwind of the formation of O3 such as Santa Clarita, Crestline, Banning, Perris, Rubidoux, and San Bernardino areas tend to have much higher concentrations. The sites which recorded the highest 2008 O3 concentrations

include: Central San Bernardino Moun tains (Crestline), Central San Bernardino Valley 1 (Fontana), Santa Clarita, Central San Bernardino Valley 2 (San Bernardino), East San Gabriel Valley 2 (Gle n dora), North West San Bernardino Valley (Upland), East San Bernardino Valley (Redlands), and Banni ng. The preceding seven sites are representative of high concentration sites for O3.

Bac k ground site designations are typically coastal areas. The following sites recorded the lowest O3 concentrations in 2008: South West Coastal LA County (LAX Hastings ), Coastal LA County (North Long Beach), North Orange County (La Habra), Central Orange County (Anaheim), and South San Gabriel Valley (Pico Rivera 2). LAX Hastings and North Long Beach recorded the lowest concentrations and are more representative of bac kground concentrations. As

me n tioned earlier, population trends show increasing development and population in the inland area. In general, the western sites in the O3 monitoring network provide lower value information than those inland sites to the north or east. The O3 monitoring network/population trend is depicted in Figure 3.48 Spatial Scale of Representativeness Monitoring objectives are matched with specific spatial scales of representativeness as shown in Table 1 8. When compared to the U.S. E PA criteria, some potential changes in monitoring objectives may be possible within

the South Coast AQMD O3 network. The LAX Hastings and North Long Beach site record low concentrations of O3 and may be more consistent with background

concentrations at th e urban scale of representativeness. Other factors such as nearby roadways may also contribute to low O3 levels at North Long Beach.49 Individual site assessments of the Spatial Scale of Representativeness for O3 are

shown in Table 18

.

Correlation Analysi s The correlation matrix analysis shows the correlation, relative difference, and distance between sites. The shape of the ellipses represents the Pearson Squared Correlation between sites with a circle representing zero correlation and a straight

line re presenting perfect correlation; correl a tion between the sites represents the degree of relatedness. The correlation however, does not indicate if one site measures concentrations substantially higher or lower than another, for this the color of the ellips es represents the average relative difference. This analysis aids

in dete r mining sites that are redundant. Confounding factors affecting analysis include AQS site data with < 75% completion is not used.

O3 correlation for 2008 between sites in Los Ange les, Orange, Riverside, and San Bernardino counties are shown in Figure 4. Site pairs that result in correlations greater than 0.8 and relative differences less than 0.3 for O3 are:

60370002 (Azusa) with 060370016 (Glendora) 060371701 (Pomona)

0603720 05 (Pasadena) 060710004 (Upland) 060712002 (Fontana).

060370016 (Glendora) with 060371701 (Pomona) 060372005 (Pasadena) 060711004 (Upland) 060712004 (Fontana)

060371002 (Burbank) with 060371103 (Central LA) 060372005 (Pasadena).

060371103 (Central L.A.) with 060371602 (Pico Rivera 2) 060372005 (Pasadena).

060371701 (Pomona) with 060372005 (Pasadena) 060658001 (Rubidoux) 060711004 (Upland) 060712002 (Fontana) 060719004 (San Bernardino)

0605900 07 (Anaheim) with 060595001 (La Habra)

060650012 (Banning Airport) with 060651016 Torres Martinez (Indian Reservation not operated by South Coast AQMD )50 060658001 (Rubidoux) with 060712002 (Fontana) 060714003 (Redlands) 060719004 (San Bernar dino)

060711004 (Upland) with 060712002 (Fontana)

060712002 (Fontana) with 060714003 (Redlands) 060719004 (San Bernardino)

060714003 (Redlands) with 060719004 (San Bernardino).

This analysis shows that for O3, many sites generate comparable d ata. This result is expected for ozone given the regional nature of the pollutant and the density of the current network. Even if sites measure somewhat comparable ozone levels, the need for public reporting of health alert and AQI levels necessitates a relatively dense ozone network to capture spatial variability. Clusters of sites with generally hig h est correlations, small average differences, and close proximities include Fontana/Redlands/San_Bernardino/Rubidoux, Azusa/Glendora/Pomona/Upland/Fontana , and Anaheim/La Habra.

O3 Minimum Monitoring Requirement U.S. EPA criteria specify the minimum number of sites required in an air monitoring network based on MSA population and design value. Design values currently exceed the standard and population d ata was taken from the 2000 census to determine the required number of samplers for the SCAB and are shown in

Table 19 . The information shows that the South Coast AQMD air monitoring network significantly exceeds the required minimum numbers of samplers f or O3.

Table 19 Minimum O3 Requirement

MSA Min. #

Monitors Required #

Monitors

A c tive

31100 4 17

40140 2 13

Carbon Monoxide Carbon monoxide (CO) is a colorless, odorless gas that is formed when carbon in fuel is not burned completely. It is a compo nent of motor vehicle exhaust, which contributes about 56 pe r cent of all CO emissions nationwide. In cities, 85 to 95 percent of all CO emissions may come from motor vehicle exhaust. The highest levels of CO in ambient air typically occur during the cold er months of the year when inversion conditions are more frequent. South Coast AQMD operates 26 sites with CO measurements as part of

the South Coast AQMD air monitoring network. Figure 5 shows the spatial distribution

of these sites.51 Regulatory Require ment Starting in the early 1970's, the EPA set national standards that have considerably reduced emissions of CO and other pollutants from motor vehicles. Since 1970,

CO emissions from on

- road v e hicles have been reduced by over 40 percent. The

greatest r eductions have been in emissions from cars (nearly 60 percent). Currently, there is no minimum requirement for the number of CO monitoring sites. Continued operation of existing SLAMS, FRM, or FEMS is required until discontinuation is approved by the EPA Regional Administrator. Where SLAMS CO monitoring is ongoing, at least one site must be a max i mum concentration site for the monitoring network.

Monitoring Objective The CO monitoring network and population trends are depicted in Figure 6. The majority of the CO monitoring network sites are designated as population exposure sites. Review of the 2008 data i n dicates that Lynwood and Central Orange County (Anaheim) sites recorded the highest 8

- hour average for CO in 2008 as 4.3 ppm and 3.6 ppm respectivel y. The Lynwood air monitoring loc a tion was replaced in 2008 by the Compton location due to unstable infrastructure and after concurrent sampling showed that CO levels were comparable at the two sites. The lowest recorded values include the Palm Springs, Lake Elsinore, Santa Clarita, and Saddleback Valley (Mission Viejo) sites. The Compton site is consistent with high concentration levels of CO. The lowest levels are found at Palm Springs, Lake Elsinore, Santa Clarita, and Mission Viejo. All sites othe r than Compton and Anaheim are consistent with population exposure. The majority of sites remain on the west side where population growth has remained relatively stagnant. CO measurements in general are of lower value given the

attainment status of the b asin and the low design values. However, the prospect of new CO NAAQS adds value in terms of tracking long

- term trends and spatial variability.52 Spatial Scale of Representativeness Most sites are consistent with the appropriate CO spatial scale of

repr esentativeness for the monitoring objective. Comparison of EPA criteria with

Table 20 shows the LAX Hastings, Pasadena, Pomona, Rubidoux, and San

Bernardino sites could be re

- de s ignated at different spatial scales that may be

more consistent with monitori ng objectives.

Correlation Analysis Correlation analysis was not available for CO using EPA provided tools. This is due to the lack of a minimum number of required monitoring sites.

Minimum Number of Sites Required For the CO monitoring network, there m ust only be one site designated as maximum concentration (Compton). All others may be considered for closure by53 demonstrating either attainment has been reached and expected to be maintained, a monitor is consistently low relative to other monitors, a mo nitor has not measured a violation with NAAQS, a monitor has siting issues, a monitor is upwind of the urban area, or a site has logistical problems beyond agency control.

EPA criteria specify minimum numbers of sites required in an air monitoring

network based on MSA population. Population data was taken from the 2000 census to determine the required number of samplers for the SCAB and are shown

in Table 2 1 . The information shows that the South Coast AQMD air monitoring network significantly exceeds the required minimum numbers of samplers for

CO.

Table 21 Minimum CO Requirement

MSA Minimum Number

of Monitors Required Number of

Monitors Active

31100 0 17

40140 0 9

Nitrogen Dioxide Nitrogen dioxide (NO2) is one of a group of highly reactive gases known as "oxides of

nitr o gen," or "nitrogen oxides” (NOx). Some NO2 is emitted directly but most NO2 forms in the atmosphere from the NO emissions from cars, trucks, buses, power plants, and any high

- temperature combustion process. In addition to contrib uting to the formation of ground

- level O3 and fine particle pollution, NO2 is linked with a number of adverse effects on the respiratory system. The South Coast AQMD operates 26 sites as part of the NO2 monitoring network. The spatial di s tribution of NO2 monitors is shown in Figure 7. Review of 1992 through 2009 data indicates that the annual NAAQS for

NO2 was not exceeded.

Regulatory Requirement As of 2009, there was no minimum requirement for the number of NO2 monitoring sites. Continued operation of existing SLAMS sites is required until discontinuation is approved by the U.S. EPA Regional Administrator. Where SLAMS NO2 monitoring is ongoing, at least one site must be a ma x imum concentration site for the monitoring network.

On February 9, 2010, E PA made revisions to the NO2 NAAQS requiring monitoring where ma x imum NO2 concentrations are expected to occur, including within 50 m of major roadways, as well as monitors sited to measure the area

wide NO2 concentrations that occur more broadly across co mmunities. To accomplish this, a two

- tiered monitoring network is proposed for the NO2 NAAQS. One tier (the near

- road network) will reflect the much higher NO2

concentrations that occur near

- road and the second

- tier (area

- wide) characterizes

the NO2 conc entrations that occur in a larger area such as neighborhood or urban54 areas. However, these new NAAQS and monitoring regulations for NO2 are not

considered in this assessment.

Monitoring Objective There is no minimum requirement for the monitoring for NO2 , but the U.S. EPA Regional Administrator must approve any reduction of the current operating monitoring network. The current NO2 monitoring network and population trends are shown in Figure 8. The majority of the NO2 monitoring network is designated as population exposure sites. A review of data indicates that the highest 1

- hour concentrations in 2008 were recorded at the North Long Beach, Lynwood, and Central LA monitoring locations and the lowest concentrations were recorded at the Palm Springs and La ke Elsinore sites. During 2008, the Lynwood site was moved to the Compton l o cation. The North Long Beach, Compton, and Central LA sites are more representative of high concentration sites than population exposure. The remainder of the sites are represen tative of population exposure. Monitors are distributed primarily in the western portion of the basin where higher NO2 levels are expected. Given the attainment status of the basin and the low ambient levels, these monitors are generally of lower value. However, the new 2010 NAAQS and monitoring requirements add value in terms of long

- term trends and spatial variability.55 Spatial Scale of Representativeness Most sites were consistent with NO2 spatial scale of representativeness. Comparison of Table 2 2 with EPA criteria showed that the LAX Hastings, and Pomona sites could be designated at spatial scales that are more consistent with monitoring objectives. North Long Beach is more representative of a high concentration site at the neighborhood scale. T he remainder of the sites are representative of population

- oriented sites at the neighborhood scale.

Correlation Analysis Correlation analysis was not available for NO2 using EPA provided tools. This is due to the lack of a minimum number of required mon itoring sites.56 Minimum Number of Sites Required For the NO2 monitoring network, there must only be one site designated as maximum concentration. All others may be considered for closure by demonstrating either attainment has been reached and expected t o be maintained, a monitor is consistently low relative to other monitors, a monitor has not measured a violation with NAAQS, a monitor has siting issues, a monitor is upwind of the urban area, or a site has logistical problems beyond agency control.

EPA criteria specify minimum numbers of sites required in an air monitoring network based on MSA population. Population data was taken from the 2000 census to determine the required number of samplers for the SCAB and are shown

in Table 2 3 . The information s hows that the South Coast AQMD air monitoring network significantly exceeds the required minimum numbers of samplers for NO2. Also included in the table is the new requirement for near roadway monitoring which is to begin operation by January 1, 2013.

Ta ble 23 Minimum NO2 Requirement

MSA Minimum

Number of

Monitors Required Number of

Monitors

Active New Minimum

Requir e ment

Near Roadway Area Wide

31100 0 17 2 1

40140 0 9 2 1

Sulfur Dioxide Sulfur dioxide (SO2) is one of a group of highly reactiv e gasses known as oxides of sulfur (SOx). The largest sources of SO2 emissions are from fossil fuel combustion at power plants and other industrial facilities. Smaller sources of SO2 emissions include industrial processes such as extrac t ing metal from or e and the burning of high sulfur containing fuels by locomotives, large ships, and non

- road equipment. South Coast AQMD operates SO2 monitors at 7 sites. Figure 9 shows the spatial distribution of the sites. The monitors are clustered mostly in the area s where SO2 sources may be located. The federal standard has not been exceeded in the basin for nearly 30 years.

Regulatory Requirement

The EPA first set standards for SO2 in 1971. The EPA set a twenty

- four hour primary standard at 140 ppb and an annual average standard at 30 ppb (to protect health). The EPA also set a 3

- hour average secondary standard at 500 ppb. Currently, there is no minimum requirement for the number of SO2 monitoring sites. Continued operation of existing SLAMS sites are required until discontinuation is approved by The U.S. EPA Regional Administrator. Where SLAMS SO2 monitoring is ongoing, at least one site must be designated a

ma x imum concentration site.

On June 2, 2010, the EPA strengthened the primary NAAQS for SO2. The E PA is also revising the ambient air monitoring requirements for SO2. States will need57 to make adjustments to the existing monitoring network in order to ensure that monitors meeting the new network design regulations are sited and operational by January 1 , 2013. However, these new NAAQS and monitoring regulations for

NO2 are not considered in this assessment.

The final monitoring regulations require monitors to be placed in Core Based Statistical Areas (CBSAs) based on a population weighted emissions inde x for the

area. The final rule r e quires:

 3 monitors in CBSAs with index values of 1,000,000 or more;

 2 monitors in CBSAs with index values less than 1,000,000 but greater than 100,000; and

 1 monitor in CBSAs with index values greater than 5,000.

Monitori ng Objective As of 2009, there was no minimum requirement for the monitoring of SO2 , but the U.S. EPA Regional Administrator must approve any reduction of the current monitoring network. The current SO2 monitoring network and population trends

are shown i n Figure 10. All SO2 monitors are desi g nated as population oriented with the exception of North Long Beach, which is designated as high

concentration as shown in Table 2 4 . A review of the annual data shows that the

maximum 1

- hour concentration in 2008 wa s .09 ppm at North Long Beach and the next highest concentr a tion was .02 ppm at LAX Hastings; the remaining sites were generally below the threshold for the monito r ing instrumentation. The majority of the SO2 sites are in the western portion of the Basin. This is appropriate, even though the population growth has occurred inland, b e cause the majority of SO2 sources are oil refineries located near the coast. North Long Beach should remain a high concentration site and the inland locations are appropriatel y designated as population oriented.

Spatial Scale of Representativeness All SO2 spatial scales of representativeness were consistent with the monitoring objectives as shown in Table 2 4

.58 Correlation Analysis Correlation analysis was not available for SO2 using EPA provided tools. This is due to the lack of a minimum number of required sites.

Minimum number of sites required For the SO2 monitoring network, there must only be one site designated as maximum concentration. All others may be considered for closure by demonstrating either attainment has been reached and expected to be maintained, a monitor is consistently low relative to other monitors, a monitor has not measured a violation with NAAQS, a monitor has siting issues, a monitor is upwind of the urban area, or a site has logistical problems beyond agency control. EPA criteria specify the minimum number of sites required in an air monitoring network based on MSA population. Population data was taken from the 2000 census to determine the requ ired number of samplers for the SCAB and are shown

in Table 2 5 . The information shows that the South Coast AQMD air monitoring network significantly exceeds the required minimum numbers of samplers for CO. Also included in the table is the new requiremen t for monitoring which is to begin operation by January 1, 2013.

Table 25 Minimum SO2 Requirement
MSA Minimum

Number of

Monitors Required Number of

Monitors

Active New Minimum

Requir e ment

Monitors Required

31100 0 5 2

40140 0 2 2

Pb

Pb is a met al found naturally in the environment as well as in manufactured products. The major sources of Pb emissions have historically been motor vehicles (such as cars and trucks) and industrial sources. As a result of the EPA's regulatory efforts to remove

Pb from gasoline, emissions of Pb from the transportation sector dramatically declined between 1980 and 1999, and levels of Pb in the air decreased by 94 percent between 1980 and 1999. Today, the highest levels of Pb in air are usually found near Pb smelters

. Other stationary sources are waste incinerators, utilities, and lead

- acid battery

manufacturers. Total Su s pended Particulate (TSP) measurements are collected at 15 sites as part of the South Coast AQMD monitoring network; five of the sites are source

o riented microscale Pb sites, and 10 sites measure population

- oriented a m bient Pb. The spatial distribution of these sites is shown in Figure 11.

Regulatory Requirement On November 12, 2008, the EPA issued final revisions to the NAAQS standards

for Pb. N ew ne t work design requirements were implemented for monitoring sources of Pb (source

- oriented mo n itoring) and urban Pb monitoring (non

- source oriented). To meet this requirement, a new source

- oriented site was established on January 1st, 2010 at the Van N uys Airport and monitoring will continue at5 9 existing sites near the Exide (Vernon), Quemetco (City of Industry), and the Trojan Battery (Santa Fe Springs) facilities.

Non source

- oriented monitors are located in urban areas to gather information on

gene ral popul a tion Pb exposure. Starting January 1, 2011, one non source

oriented monitor is required in each CBSA with a population > 500,000 as determined by the most recent census data. South Coast AQMD ’s current Pb monitoring network exceeds the minimum required monitoring specified as part of the final revision to the NAAQS for Pb.

Monitoring Objective The current Pb monitoring network and population trends are shown in Figure 12.

All of the non

- source

- oriented Pb monitoring network sites are populat ion

oriented. The Pb monitoring network was put in place when leaded gasoline was still being used in automobiles. With the mainstream use of unleaded gasoline,

conce n trations of Pb have decreased with no clear high concentration site. Therefore, all of the non

- source

- oriented Pb monitoring have been re

- designated as population

- oriented monitoring locations. The source

- oriented sites are appropriately considered source impact sites.

Spatial Scale of Representativeness The proper scale for the five s ource

- oriented sites is microscale. The scale for the

non

- source

- oriented sites are neighborhood scale or greater as shown in Table 2 6

.60 Correlation Analysis Correlation analysis was not available for Pb using EPA provided tools. This was because most ag encies across the country do not have an existing Pb monitoring

network.

Minimum Number of Sites Required EPA criteria specify the minimum number of sites required in an air monitoring network based on MSA population. Population data was taken from the 2 000 census to determine the required number of samplers for the SCAB and are shown

in Table 2 7 . Only two facilities exceed the 1.0 ton/year emissions threshold for

source

- oriented monitoring based on the latest data: Exide (Vernon) and Van Nuys Airport. The information shows that the South Coast AQMD air monitoring network significantly exceeds the required minimum numbers of samplers for Pb. Also included in the table is the new requirement for u r ban monitoring which is to begin operation by January 1, 2011.

Table 27 Minimum Pb Requirement
MSA Minimum Number of

Monitors Required Number of Monitors

Active New

Minimum

R e quirement

Source Impact Urban

Monitoring Source

Impact Urban

Monitoring Urban

Mon i toring 31100 2 0 5 6 1

40140 0 0 0 4 1

PM10 Particulate matter also known as particle pollution or PM, is a complex mixture of microscopic particles and liquid droplets. Particle pollution is made up of a number of components, i n cluding ions (such as nitrates and sulfates), organic chemicals, elem ental carbon, metals, and soil or dust particles.

The size of particles is directly linked to their potential for causing health problems. The U.S. EPA regulates particles that are 10 micrometers (  m) in diameter or less (PM10) because these pa r ticles ge nerally pass through the throat and nose and enter the lungs. Once inhaled, these particles can affect the heart, lungs and cause serious health effects. "Inhalable coarse pa r ticles," are defined as larger than 2.5  m but smaller than 10  m in

diameter.

Regulatory Requirement The nation's air quality standards for particulate matter were first established in 1971 and were not significantly revised until 1987, when the EPA changed the indicator of the standards to regulate inhalable particles smaller tha n or equal to

10  m in diameter. PM10 measurements contain both fine (PM2.5) and coarse particles. In 2006, the U.S. EPA revoked the annual PM10 standard because the available evidence did not suggest a link between long

- term exposure to PM10 and health problems. The 24

- hour PM10 NAAQS was retained as well as61 minimum monitoring requirements for PM10 based on MSA population and PM10 design value as specified in 40 CFR § 58 Appendix D.

To meet this requirement, size

- selective inlet high

- volume samplers are operated

at 22 sites to meet the requirements for PM10 FRM sampling. In addition PM10 continuous FEM analyzers are operated at 14 sampling sites providing hourly particulate concentration measurements. Figure 13 shows the spatial distribution of the sampling sites. Real

- time mon i tors, for the most part, are clustered in the high concentration areas, with two located in the desert area where wind

- blown crustal material can cause exceedances of the twenty

- four hour standard during high wind events. Real time PM10 mon itors also support ongoing health studies in the region. All PM10 FRM monitors currently operate on a one

- in

- six day schedule with the exception of Indio and Rubidoux, the maximum concentration sites in each air basin, which operate on an enhanced frequen cy one

- in

- three day schedule as required by 40 CFR § 58.12(e). The continuous PM10 FEM monitors also provide a daily record of PM10 values at many of the higher concentration

sites.

Monitoring Objective The majority of the PM10 sites are designated a s population exposure sites as

shown in Table 2 8 . The 2007

- 2008 data shows that Mira Loma (Van Buren) reported the highest concentrations in the South Coast Basin at 142 and 135

 g/m 3 in 2007, and 2008 respectively (excluding exceptional events). This site began operation in 2006, and previous to that, Rubidoux was designated as the maximum concentration site requiring enhanced monitoring frequency as per 40 CFR § 58.12(e) based on 2000

- 2005 monitoring data. This assessment concludes that based on recent years monitoring data, Mira Loma will be designated the maximum concentration site and the required enhanced monitoring frequency will be provided by a continuous PM10 FEM BAM r ecently installed at the site. The remainder of the PM10 sites are consistent with population exposure at the neighborhood scale. Figure 14 shows the distribution of the PM10 monitors along with the population change from 1990 through 2009. Sites are co ncentrated inland, where particulate concentrations tend to be higher.62 Spatial Scale of Representativeness The vast majority of sites showed consistency between the spatial scale of

represent a tiveness and monitoring objective. The North Long Beach sit e was designated at the middle scale but with a population

- oriented monitoring objective. Population

- oriented sites are more consistent with the neighborhood scale of representativ e ness.

Correlation Analysis PM10 correlation analysis for data collected d uring 2008 between sites in Los Angeles, Orange, Riverside, and San Bernardino counties are shown in Figure 15. Site pairs with correl a tions greater than 0.8 and relative differences less than 0 .3

for PM10 are:

060370002 (Azusa) with 060710025 (Ontari o)63 060370016 (Glendora) with 060711004 (Upland)

060658001 (Rubidoux) with 060658001 (Norco)

0600658005 (Mira Loma VB) with 060658001 (Rubidoux)

060712002 (Fontana) with 060710025 (Ontario)

060719004 (San Bernardino) with 060712002 (Fontana)

Th is analysis shows that for PM10, few sites correlate in low concentration areas. The greatest correlation was found between Rubidoux and Mira Loma (Van Buren), the two sites with the highest 24

- hour PM10 concentrations in the Basin.

Minimum Number of Sit es Required EPA criteria specify the minimum number of sites required in an air monitoring network based on MSA population and design value. Population data was taken from the 2000 census to determine the required number of samplers for the SCAB

and are s hown in Table 2 9 . The information shows that the South Coast AQMD air monitoring network significantly exceeds the minimum required number of samplers for PM10.

Table 29 Minimum PM10 Requirement
MSA Min. #

Monitors Required #

Monitors

A c tive

31100 2 9

40140 3 16

PM2.5 Particulate matter, also known as particle pollution or PM, is a complex mixture of extremely small particles and liquid droplets. Particle pollution is made up of a number of components, i n cluding ions (such as nitrates and sulfate s), organic chemicals, elemental carbon, metals, and soil or dust particles. Fine particles, such as those found in
smoke and haze, are 2.5  m in diameter and smaller. These particles can be directly emitted from sources such as mobile sources, meat cook ing and forest fires, or they can form when gases emitted from power plants, industries, and automobiles react in the air.

Regulatory Requirement The nation's air quality standards for particulate matter were first established in 1971 and were not signifi cantly revised until 1987, when the EPA changed the indicator of the standards to regulate inhalable particles smaller than or equal to 10 um in diameter. Ten years later, after a lengthy review, the EPA revised the PM standards, setting separate standard s for fine particles (PM2.5) based on their link to serious health problems including increased symptoms, ho s pital admissions, emergency room visits, and premature death for people with heart64 and lung disease. The regulation also required local agencies t o operate a minimum number of PM2.5 monitoring sites as specified in 40 CFR § 58 Appendix D.

To comply with regulatory requirements, a network of 17 Federal Reference Method (FRM) samplers was first deployed in early 1999. In December 1999, a

second Coac hella Valley PM2.5 sampling site was established in Palm Springs. On June 20, 2003, PM2.5 sampling began at the South Long Beach location. The final addition to the PM2.5 FRM network occurred in October 2005 at the newly established Mira Loma (Van Buren) site. The current number of PM2.5 FRM

sa m pling sites remains at 20 and is depicted in Figure 16.

Prior to 2009, a network of continuous PM2.5 monitors was in operation, although they did not have FEM status. In January 2009, a network of seven

PM2.5 FEM monitors were deployed and designated as Special Purpose Monitors (SPM) in order to provide time for comparison to collocated FRM samplers. The

two

- year maximum SPM status expires at the end of 2010 and comparability analysis will be completed before tha t time. A network of ten non

- FEM PM2.5 continuous monitors continues operation.

Monitoring Objective The PM2.5 monitoring network is shown in Figure 17 along with population trend from 1999 through 2009. Most PM2.5 sites are designated as population exposure at the neighborhood scale. Review of 2008 data shows that Central Los Angeles, Anaheim, Pasadena, South Long Beach, Rubidoux, Burbank, and North Long Beach recorded the highest concentrations of PM2.5. The lowest value

recorded was at the Palm S prings monitoring location, which is more consistent with a regional transport site rather than a population

- oriented site.65 Spatial Scale of Representativeness All PM2.5 spatial scales of representativeness were consistent with the monitoring objectiv es as shown in Table 30

.

Correlation Analysis PM2.5 correlation for 2008 between sites in Los Angeles, Orange, Riverside, and San Bernardino counties are shown in Figure 18. Data for 2008 was used because it was the most recent complete data set for the South Coast AQMD PM2.5 monitoring network. Site pairs with co rrelations greater than 0.8 and relative

differences less than 0.3 for PM2.5 are:

060370002 (Azusa) with 060372005 (Pasadena) 060658001 (Rubidoux) 060374002 (North Long Beach) with 06 0374004(South Long Beach) 060651003 (Riverside Magn o lia) with 060658001 (Rubidoux)66 060710025 (Ontario) with 060712002 (Fontana) 060712002 (Fontana) with 060719004 (San Bernardino)

This analysis shows that for PM2.5, a number of clusters have a hi gh level of correlation and a low average relative diffe r ence.

Minimum Number of Sites Required EPA criteria specify minimum numbers of sites required in an air monitoring network based on MSA population and measured concentrations. Population data

was t aken from the 2000 census to determine the required number of samplers for

the SCAB and are shown in Table 31 . The information shows that the South Coast AQMD air monitoring network exceeds the required minimum numbers of samplers for PM2.5.

Table 31 Minimum PM2.5 Requirement

MSA Minimum

Number of

Monitors Required Number of

Monitors

Active

31100 6

- 10 12

40140 6

- 10 1167 Figure 2 South Coast AQMD O3 Monitoring Locations68 Figure 3 O3 Monitoring Locations and Change in Population 1990 Through 200969 Figure 4 200 8 Los Angeles, Orange, Riverside, and San Bernardino County O3 Site C orrelation70 Figure 5 South Coast AQMD Monitoring Locations for CO71 Figure 6 CO M onitoring L ocations and C hange in P opulation 1990 T hrough 200972 Figure 7 South Coast AQMD Monitoring Locations for NO273 Figure 8 NO2 M onitoring L ocations and C hange in P opula tion 1990 T hrough 200974 Figure 9 South Coast AQMD Monitoring Locations for SO275 Figure 10 SO2 M onitoring L ocations and C hange in P opulation 1990 T hrough 200976 Figure 1 1 South Coast AQMD Source and Ambient Pb Monitoring Locations77 Figure 12 Pb M onitoring L ocations and C hange in P opulation 1990 T hrough 200978 Figure 13 South Coast AQMD PM10 Monitoring

Locations79 Figure 14 PM10 M onitoring L ocations and C hange in P opulation 1990 T hrough 200980 Figure 15 2008 Los Angeles, Orange, Riverside, and San Bernardino County PM10

correlation81 Figure 16 South Coast AQMD PM2.5 Monitoring Locations B = BAM FEM

B1 = BAM82 Figure 17 PM2.5 M onitoring L ocations and P opulation C hange 1999 T hrough 200983 Figure 18 2008 L os Angeles, Orange, Riverside, and San Bernardino County PM2.5

correlation848586



## IV. POTENTIAL SOUTH COAST AQMD NETWORK CHANGES

AND RECOMMENDATIONS

OVERVIEW
This section describes potential changes to the South Coast AQMD air monitoring network that would help to address the findings of the site

- by

- site assessments (Section II) and the pollutant network assessments (Section III). The overall goal of these potential modifications to the network design is to improve the ability to achieve multiple monitoring objectives whi le ensuring the efficient use of resources.

Note that t he current AQMD air monitoring network meets or exceeds U.S. EPA monitoring requirements and satisfies multiple monitoring purposes. The dense network of monitoring locations covering a wide area pro vides the necessary data for NAAQS attainment decisions. It also provides a robust data set for air quality model validation, trend analysis, health studies, and

real

- time public communication of air quality status. The AQMD places a high value on all

th ese monitoring purposes, all of which must be carefully considered before network changes are

made.

Many of the findings described in the previous sections are site

- specific issues that are addressed by South Coast AQMD on an ongoing basis. Thes e include site infrastructure improvements and alterations such as vegetation trimming, soil stabilization or paving, replacement of shelters, moving probes and inlets to meet appropriate setback criteria, and increasing or improving power supplies. Throu gh the Annual Network Plan and regular audit and maintenance schedules, issues such as these are continually being identified and addressed. However, when such issues cannot be addressed due to logistical constraints, then the value and monitoring objecti ves of a particular site could be reconsidered. Furthermore, the monitoring objectives and spatial scales of all sites are assessed as part of the Annual Network Plan, ensuring U.S. EPA minimum monitoring requirements are satisfied. Therefore, relatively minor changes to site infrastructure and monitoring objective/spatial scale designations are not explicitly addressed in this section, although these factors are important in determining the value of a site within a larger pollutant monitoring network.

W hat follows are some potential network modifications that address larger issues such as redundancies, gaps, efficiencies, and synergies within and between the South Coast AQMD pollutant monitoring networks. A summary of recommended network modifications t o the South Coast AQMD monitoring network is provided at the end of this section. Note that there are many purposes for air quality monitoring, some beyond those described in this assessment. Closing, moving or creating monitoring sites requires signific ant resources and often a long period of concurrent monitoring to show comparability. Thus, these suggestions must be weighed against many other factors before being implemented.



### SO2, NO2, AND CO MON ITORING NETWORKS

The South Coast AQMD monitoring netwo rk far exceeds the minimum monitoring requirements for SO2, NO2, and CO, and South Coast AQMD areas are currently in attainment of the NAAQS87

for these pollutants. As of 2009, there were no minimum monitoring requirements for these criteria pollutants. In 2010, minimum monitoring requirements were added for NO2 and SO2, and these new regulations will require changes to the NO2 network by 2013. New NAAQS and monitoring regulations for CO are also anticipated with possible network modifications required.

In all cases, South Coast AQMD measurements of SO2, NO2

, and CO are made at monitoring sites that are also part of the more essential O3 and PM monitoring networks for which the basin is not in attainment with the NAAQS. Thus, the cost of continuing to m onitor for these pollutants is relatively low given that the site infrastructure and staff resources dedicated to the sites will continue as part of the PM and O3 networks. However, there are costs associated with the maintenance, calibration, replacement , and auditing of the SO2, NO2, and CO instruments as well as the resources required to validate and submit the data to U.S. EPA.

Given the recent and upcoming revisions to monitoring regulations for these pollutants, a reduction in the number of SO2, N O2, and CO monitors in the network is not recommended until network design decisions to meet the new requirements have been made. For instance, new NO2 sites will be needed near roadways and possibly in EJ areas. The shifting of resources to

accommodate these new requirements will affect the current network configuration.

Once the new regulations for CO are final and network design decisions for NO2 and SO2 have been made, a reconsideration of the extent of the SO2, NO2, and CO networks is recommended. It is likely that the future South Coast AQMD monitoring networks for these pollutants will continue to exceed minimum requirements in order to meet other objectives such as model validation, maintenance plan requirements, and trend analysis. A careful co nsideration of these factors along with the costs of continued operation may lead to more efficient and effective monitoring networks for SO2, NO2, and CO.



### OZONE MONITORING NET WORK

South Coast AQMD exceeds the minimum monitoring requirements for the O3 m onitoring

network. Due to the large population in Southern California and the complexity of the geography and meteorology, a relatively large number of air monitoring stations are needed to adequately describe air quality in South Coast AQMD ’s jurisdictio n and provide important health information to the public. Both South Coast AQMD air basins (South Coast and Coachella Valley) are designated non

- attainment for O3, and a wide, robust O3 network is critical for accurate assessment and modeling efforts.

Ho wever, as a regional pollutant, O3 concentrations generally do not vary significantly on short spatial scales, the exception being near busy roadways where NO titration occurs. Based on the correlation analysis in Section III, some sites in close proximit y to one another provide very similar O3 readings. Three clusters of high similarity identified in Section III were:

 Fontana/Redlands/San Bernardino/Rubidoux

 Azusa/Glendora/Pomona/Upland/Fontana88

 Anaheim/La Habra

In terms of siting criteria, findings r elated to these sites included:

 La Habra

- is within 3 m of cypress trees surrounding inlet probe and does not meet distance from traffic lane requirement.

 Pomona

- is less than the required distance from roadway.

Other assessment findings regarding th ese sites include:

 Glendora has been in operation for 30 years and was originally a CARB monitoring location. There have been difficulties securing a long

- term rental contract and the City of Glendora requirements have made it difficult to upgrade the mo nitoring shelter. The site lacks adequate space and infrastructure to expand at the current location.

 La Habra has been in operation for 50 years; however, it lacks adequate space and infrastructure to expand to include particulate monitoring. The site has not typically been used for research or air toxics studies and there are few synergies at the site between air monitoring programs.

 Pomona has been in operation for 45 years ; h owever, it lacks adequate space and infrastructure to expand. The data ha s not typically been used for research or air toxics studies and the site was originally intended as a micro

- scale CO location. There are few synergies between air monitoring programs at this location.

The Fontana/Redlands/San Bernardino/Rubidoux cluster is well spaced in an area of generally the highest O3 levels in the basin. It is important to continue to monitor in this area and have a good spatial distribution of O3 levels given the frequent exceedances and need for public health

advisories. Theref

ore, no changes are recommended to these O3 sites.

The Azusa/Glendora/Pomona/Upland cluster (excluding the more distant site Fontana) is geographically compact showing high degree of comparability in O3 measurements. In 2007 and 2008, Upland recorded the most exceedances of federal and state air quality standards of O3, although this area is no longer the highest O3 region in the basin. The Glendora site is only seven km from the Azusa site, and although it can record higher O3 levels than Azusa, reading s are typically lower than Upland. The Pomona site is also relatively close to both Upland and Azusa. Upland and Azusa have been active sights for 37 and 53 years respectively providing the needed long

- term trends. Given the proximity to other correlate d stations and the siting and infrastructure issues mentioned above, both Glendora and Pomona could be considered potentially redundant in terms of O3 measurements.

The Anaheim/La Habra cluster show similar but relatively low levels of O3 according to rec ent data and the correlation analysis. Given these low levels, the unresolvable siting issues, and the few other measurements made at La Habra (CO and NO2 only), this site would be another potential candidate for reduction in size of the O3 network.89

If O 3 measurements cease at both La Habra and Pomona, a geographical gap might be created in northwestern Orange County. South Coast AQMD headquarters in Diamond Bar is at the center of that gap, and a new site at headquarters would fill the potential need fo r additional O3 measurements in the area while providing considerable efficiencies with a convenient location.

Two other changes to the O3 network are already underway. First, the Mira Loma Van Buren monitoring location was established as a replacement site for the Mira Loma Jurupa monitoring location. Ozone data for Jurupa was not included in the correlation analysis as it is not in the AQS database. The closure of the Jurupa station is planned within the coming year. Second, a

new site in Temecula i s already in place with O3 measurements planned. It is in an area that has grown significantly in recent years and may not be adequately represented by the current O3 monitoring network.



### PM2.5 MONITORING NET WORK

The South Coast AQMD monitoring network e xceeds the minimum monitoring requirements for

PM2.5. Due to the large population in Southern California, the complexity of the geography,

and the non

- attainment status of the basin, a relatively large number of air monitoring stations are needed to adequ ately describe air quality and provide important health information to the public.

As a generally regional pollutant, PM2.5 concentrations generally do not vary significantly on short spatial scales unless very near strong sources of particulate matter. Based on the correlation analysis in Section III, some sites in close proximity to one another provide very similar PM2.5 readings. Two clusters of high similarity identified in Section III were:

 San Bernardino/Rubidoux/Fontana

 North Long Beach/South Lo ng Beach

In terms of siting criteria, findings related to these sites included:

 Fontana is within 9 m of unpaved parking and within 9 m of regularly idling diesel

exhaust.

 South Long Beach does not currently meet all 40 CFR § 58 Appen dix E Probe S iting

C riteria, specifically the spacing from obstructions surrounding the instrumentation.

Other assessment findings regarding these and other sites include:

 Big Bear Lake has been in operation for 11 years and was originally established to

determine the ext ent of winter wood smoke particulate matter. Since that time, there have not been exceedances of the standard. It is the only measurement made at the site and thus there are no synergies between monitoring programs. Consideration must be given to the re moteness of the location and the cost to maintain the site.90

 Fontana has been in operation for 29 years. However, the site lacks adequate space and infrastructure to expand at the current location.

 South Long Beach was established June 2003 to monitor pa rticulate influence from port activities. The infrastructure of the facility meets the needs of particulate sampling, but there are no facilities for continuous analyzers and no room for expansion. There are no synergies between air monitoring programs o r use of office space by inspectors. The cost to relocate the site is low due to the low number of samplers and there is potential to move this site to a location nearer to port activities.

The San Bernardino/Rubidoux/Fontana cluster is relatively well s paced in an area of generally the highest PM2.5 levels in the basin. It is important to continue to monitor in this area and have a good spatial distribution of PM2.5 levels given the frequent exceedances and need for public health advisories. Despite s ome potential siting issues at Fontana, no changes are

recommended to these PM2.5 sites.

The North Long Beach/South Long Beach cluster is geographically compact with only four miles separating the sites. Data at the two sites is similar in terms of corre lation, exceedances,

averages
, and maximum levels. The South Long Beach location was intended to measure the impact of the nearby port activities. However, no site closer to the Port area could be secured at the time. In 2007, a site for a temporary air monitoring study was secured much closer to Port activities, and this site is still available to be made permanent with sufficient infrastructure for expansion. Given the limitations of the current South Long Beach site with no room for gaseous

measureme nts, and the original intended purpose of the site, the temporary site on Anaheim Street in Long Beach may be a better option. Therefore, a potential modification of the PM2.5 network is to move the South Long Beach measurements to this new site closer to the Port activities. Concurrent monitoring may need to be conducted to show that the new site records similar or higher PM2.5 levels than the current site.

The Big Bear Lake monitoring location only measures PM2.5, and has not been in violation of

the 2 4

- hour or annual PM2.5 NAAQS in 2007 or 2008. Sampling only occurs on a reduced, U.S. EPA approved, sampling frequency of one

- in

- six day due to the remote location. The original intent of the site was to determine if wintertime residential wood burning co uld lead to NAAQS

violations. Given that violations have not been observed and that the remote location of the site requires significant staff resources to maintain even at the reduced sampling schedule, the value

of the site should be reconsidered.

Another suggested change in the configuration of the PM2.5 network is to continue the transition to continuous PM2.5 FEM monitors. Currently, these monitors are being run collocated with

FRM filter

- based measurements to establish comparability and determ ine any biases. Once complete, the FEM continuous monitors can replace many existing FRM monitors in the network. This will reduce the considerable resources required to maintain the aging FRM samplers and to process and weigh the collected filter sample s. It will also provide for daily data at sites that may only be one

- in

- three day sites currently, and it will provide useful hourly data for public reporting and air quality assessments.91



### PM10 MONITORING NETW ORK

The South Coast AQMD monitoring netw ork exceeds the minimum monitoring requirements for

PM10. Due to the large population in Southern California, the complexity of the geography, and

the current non

- attainment status of the basin, a relatively large number of air monitoring stations

are nee ded to adequately describe air quality and provide important health information to the public.

PM10 includes PM2.5, but concentrations can vary significantly on short spatial scales. However, based on the correlation analysis in Section III, some sites i n close proximity to one another provide similar PM10 readings. These sites tend to be in the highest concentration areas (Rubidoux and Mira Loma Van Buren), but the correlated site clusters are not as clear as for O3

and PM2.5.

In terms of siting crit eria, findings related to PM10 sites include:

 South Long Beach does not currently meet all 40 CFR § 58 Appendix E P robe Siting

C riteria, specifically the spacing from obstructions surrounding the instrumentation.

Other assessment findings regarding thes e and other sites include:

 Norco has been in operation for 30 years. The infrastructure is inadequate as there are no indoor facilities which allow for monitoring of criteria pollutants. Data is not used for purposes other than NAAQS and there are no ot her measurements being made at the site.

 Ontario Fire Station

– has been in operation for 11 years. The infrastructure is inadequate as there are no indoor facilities which allow for monitoring of criteria pollutants. Data are not used for purposes oth er than NAAQS and there are no synergies between

programs.

Given the high levels of PM10 recorded at both Rubidoux and Mira Loma, no changes are recommended for PM10 measurements at these sites, despite their high level of correlation. However, given tha t Mira Loma has consistently recorded higher levels of PM10 over the last five years than Rubidoux, the Mira Loma site should be designated as the expected maximum concentration PM10 site as per 40 CFR § 58.12(e).

The only measurement at the Norco site is PM10 and thus does not provide any synergies with other programs. It consistently records lower PM10 concentrations than nearby Rubidoux and Mira Loma. Therefore, it can be considered for potential elimination from the PM10 monitoring

network. A simila r analysis can be made for the Ontario station, with few synergies with other programs and very similar PM10 statistics levels to Norco and other nearby sites. If both sites were eliminated, this may create a geographical gap in western Riverside and San Bernardino Counties. To provide spatial coverage in that area, the sites could be consolidated into a new

location with better infrastructure between the current Norco and Ontario sites.92

The potential move of the South Long Beach site closer to port act ivities suggested for the

PM2.5 network also holds for the PM10 network.

Another suggested change in the configuration of the PM10 network is to transition towards continuous PM10 FEM monitors. New continuous PM10 monitors have recently been deployed

f or a regional health study and can eventually serve to replace many existing FRM monitors in the network. This will reduce the considerable resources required to maintain the aging FRM samplers and to process and weigh the collected filter samples. It w ill also provide for daily data at sites that may only be one

- in

- six day sites currently, and it will provide useful hourly data for public reporting and air quality assessments.



### SUMMARY OF RECOMMEND ED NETWORK MODIFICAT IONS

The current AQMD air monitorin g network meets or exceeds U.S. EPA monitoring requirements

while satisfying a wide array of monitoring purposes, some beyond those described in this assessment. Meeting minimum monitoring requirements is just one factor in determining the

value of sites and measurements. Given the challenges of meeting air quality standards in Southern California and the need for information to help in developing control strategies to achieve attainment, the South Coast AQMD monitoring network will continue to far excee d the minimum requirements. Furthermore, closing, relocating or creating monitoring sites requires significant resources and often a long period of concurrent monitoring to show comparability. Thus, the suggestions summarized below must be weighed again st many other factors before being implemented. Most changes to the monitoring network are subject to approval by the U.S. EPA Regional Administrator.

 Once new monitoring regulations, attainment status, and network decisions are known for SO2, NO2, and C O, consider a general reduction in the number of sites monitoring for those pollutants in the network while still meeting all monitoring objectives and

purposes.

 Reconsider the values of the Glendora, La Habra and Pomona sites, and potentially

consolidate measurements at nearby sites or at a new site in Diamond Bar.

 Reconsider the value of the Big Bear Lake PM2.5 site.

 Consider moving all South Long Beach measurements to a new permanent site on Anaheim Street in Long Beach that is closer to port activiti es and will better achieve the original purpose of the site.

 Reconsider the value of the Norco and Ontario particulate sites, and potentially consolidate measurements at nearby sites or at a new site between the two.

 Continue to transition to continuous PM measurements that can eventually replace filter

based measurements.